Category Archives: Newsletter

Why are my SPF Pass Rates so low?

SPF is an important technology for email delivery.  If your email is not SPF compliant, then it is highly unlikely that an Inbox Provider will deliver the email to the recipient’s inbox.  Inbox Placement is key to getting your message heard and SPF compliance is key to making the Inbox.  MxToolbox Delivery Center provides a comprehensive resource for understanding and managing SPF, DKIM and DMARC compliance, but there are few things you need to know about SPF regardless of the tools you choose.

SPF Compliance

To be SPF Compliant, an email must SPF Authenticated and SPF Aligned.  The standard provides a strict compliance that also allows a domain to designate 3rd parties as valid senders.

SPF Authentication

An email is considered SPF Authenticated when the email originates from an SMTP server on an IP address that is contained in the sending domain’s SPF records.  This enables a business to designate a 3rd party emailer as a valid sender of email.  

SPF Alignment

SPF uses the header of the email to determine Alignment.  An email is considered SPF Aligned when the domain in the “From:” address of the email is the same as the domain in the Return-Path field of the header or with a domain that is Authenticated with the valid list of senders in the SPF record.

MxToolbox SPF Pass Rates

MxToolbox has two metrics useful for understanding SPF Compliance: SPF Authentication Rates for Aligned Domains and SPF Pass Rates for Verified Sources.  These metrics enable you to report upon and analyze your email providers for areas to improve upon.

SPF Authentication Rates for Aligned Domains

As part of our SPF management processes, MxToolbox Delivery Center gathers a list of valid return path domains and subdomains and analyzes the amount of email from these SPF Aligned domains that is properly SPF Authenticated.   Email that is Aligned but not properly Authenticated indicates that one or more email senders are missing from your SPF records, or that your SPF records are too large and violate SPF include rules.  You will need to add the missing senders to your SPF record or use an SPF Flattening tool.

SPF Pass Rates for Verified Sources

As part of MxToolbox Delivery Center, we automatically detect the sources that are sending email on behalf of your domain. These include your own servers, your corporate Inbox Provider, 3rd party marketing tools, CRMs, etc.  Verified Sources should be in your SPF records, meaning they should be Authenticated. 

Our second analysis looks at the SPF Alignment rates for each of these Authenticated senders – the SPF Pass Rate.  A low SPF Pass Rate for a sender indicates that the sender’s “From” and “Return-Path” domains are not the same or not contained in your SPF record.  Unknown sources that arise from this analysis could be threats to your brand or rogue senders that need to be added to your SPF records.

There are potentially several reasons for low SPF Pass Rates for Verified Sources:

  • Spoofing – A malicious actor is trying to use your domain to legitimize their spam or malware.
  • Forwarding – Many people use inbox forwarding or mailing lists to manage email distribution or aggregate email. Forwarded email will change the return-path, breaking SPF Alignment.
  • Missing Senders – Someone may have legitimately contracted with a 3rd party emailer and failed to add the full or correct entry to the SPF record. The sender could be SPF Aligned, but not Authenticated.

To fully understand why your SPF Pass Rate for a Verified Source you need to investigate the largest sources of misaligned email, SPF Unaligned Domains. Typically, you will see benign domains like,, and other subdomains of legitimate senders. Occasionally, you’ll see large volumes from other sources, which could be benign or fraud. Investigating these can improve your email delivery.

Does DMARC and email deliverability seem too complicated?

MxToolbox Experts are here with a Managed Services approach to your email configuration issues.

May Newsletter – A Customer Service Company that Happens to Provide Email & Web Security!




Most people come to to use our Free Tools or MxWatch Server Monitoring. In addition to our Free Tools and MxWatch, we also offer Business Email & Web Security Services. Both our MxWatch and Email services come with complimentary support. Our team of Support Technicians and Account Managers are dedicated to meeting your needs and addressing any concerns or questions you may have. The end goal is to build an ongoing business relationship where all of your Email, Monitoring or Web Security needs are fulfilled. Unlike some companies, we aren’t here to sell you something once and never work with you again. We strive to constantly and consistently exceed our customer’s expectations. You may ask, how do we do that?

We know that when you are having a problem with your server or email it can be very stressful. As a Consultant, System Administrator or the guy in charge of the server, you need immediate resolution as we understand that email is the lifeblood of any business. We also know how frustrating it is to call a provider and not be able to reach someone. That doesn’t happen at MxToolBox; you have a direct line to our team. Our Support Technicians work hard to listen to your issue and then provide solutions. We don’t do lip service here, we will either offer a solution or work with you until we find one.

Our Technicians are continually training and participating in continuing education so they can stay ahead of the game. Technology is changing rapidly around us and it is our obligation to understand those changes.  As your provider, it is both our responsibility and our pleasure to pass on that knowledge. We also host Forums and a Technical Blog as another way to pass on the good word.

Every business has their share of complaints and we work with our team to ensure that problems are dealt with immediately for quick resolution. We work hard to take responsibility for our mistakes and you won’t get caught in a transfer loop or passed around from one place to another. Typically your issue can be resolved with any team member that picks up the phone.

The Extra Step
Just like at your local hardware store we won’t point you to “Aisle 3” and go on with our day. Instead we take pride in leading you to the solution if possible. We’ve built online knowledge bases for all of our tools and products, we are available by phone (866-MXTOOLBOX), email, Support Ticket, Twitter, Facebook or distress signals. You can either reach out to us directly by one of the methods above or delve into our helpful documentation to find the answer yourself.

Referrals are a great sign that you are happy with our services and support. We want you to know how much we appreciate your stellar feedback and we will reward you for spreading the good word. Active customers that pass on referrals can receive a 15% discount on their next quarterly invoice. If you’re not already on one of our Business Email or Web Security Services, reference this newsletter when you contact us and we’ll offer you 10% off any new service purchase!

We are here to help you solve problems, not be another problem you have to deal with. Our team prides itself in being highly available and knowledgeable. Pick up the phone today, put us to the test, we’re standing at the ready. Stay tuned for future newsletters that will spotlight the individual members of our team (Chad, Brendan, John, Peter, Douglas, Wendy, Brian or Jeremy).


Copyright 2012 MxToolbox Inc. 12710 Research Blvd. Austin, TX 78759




April Newsletter: How MxWatch Can Help your Business

MxToolBox has offered a variety of Free Tools including our MxWatch Server Monitoring since 2003. Over the past year, we have made numerous improvements and upgrades, including the ability to monitor TCP, HTTP/HTTPs and other additional services. Just last month we released a completely revamped version of our MxWatch Dashboard. This launch didn’t change any of the behind the scenes mechanics, but provided a new way to look at the information and a better way to organize your alerts.

The majority of people come to MxToolBox as a result of a Blacklisted email server, or a host who has servers that are Blacklisted. Inclusion of your IP Address in a Realtime Black List (RBL) or Blacklist means that IP address has either sent spam or is part of a cluster of IP Addresses that are being blocked for poor sending reputation.

What does this mean for you as the small business owner and how can MxToolBox help you?
Our MxWatch Monitoring will allow you to setup Monitors for Blacklists, SMTP and more. You will then be alerted via email or SMS text if there is an issue with a Monitor, which can help you address problems before they escalate. The Free version of our MxWatch includes two Monitors, which can be used to check the Blacklist every seven days or any other additional alerts of your choice; SMTP, TCP, HTTP, etc.

We also offer Paid Services for those individuals that want to monitor more than two sites or servers. Why choose the paid services? The MxWatch Basic package provides up to 10 Monitors. You can monitor almost any part of your infrastructure; here are a few examples:

  • IP for Blacklist Problems
  • Mail Server for SMTP availability
  • Monitor your Website (HTTP/HTTPS)
  • MX records or other DNS records
  • Any TCP Port (110, 443, 993, 995 or any custom port)

Our users have shared some of the systems they are monitoring including: VoIP, Web Servers, LDAP servers, FTP, SSH, POP, IMAP, Sql server, remote desktop and more.  The possibilities are endless!Does this make your head spin?  Are you not sure what all this means and how to know what you can monitor? No problem; We even provide an Alert Wizard which allows you to enter your Email Address or Domain Name and get a summary of the different Monitors that can be setup.

Please feel free to contact our Customer Care Team by emailing or simply call 1-866-MxToolBox (698-6652) with any questions or to learn how you can put the Blacklist issue behind you forever!

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Copyright 2012 MxToolbox Inc. 12710 Research Blvd. Austin, TX 78759 

March Newsletter – Does MxToolBox Advocate the Use of Blacklists?


March Newsletter – Does MxToolBox Advocate the Use of Blacklists?

One of the most common security challenges for companies is keeping their organization’s email off of Blacklists. A Blacklist, or Realtime Black List (RBL) is simply a database of dangerous IP Addresses that email server operators can use to reject mail from sources that have been identified as sending spam.  When your company gets Blacklisted it can cause major trouble for your business and often has detrimental effects on your email delivery and the ability to reach your prospects and/or current customers; and that can mean loss of existing or potential business!People all around the world rely on our Super Tool (Blacklist Lookup) and our MxWatch Email Server Monitoring services on a daily basis to let them know if they have network problems.  We wanted to help shed a little light on blacklisting and what that means for you and your business.  We hope to answer a few common questions that we’ve recently received:

Q: Are Blacklists credible organizations?  
A: Some are; some are not.

Q: Is MxToolBox a credible organization?  
A: Absolutely!  We are here to help you understand blacklists and how they can affect your business. We also understand how time consuming they can be and we are here to offer you a solution!

Q: Does inclusion of a blacklist on the MxToolBox Super Tool have any effect on my email delivery?  
A: Absolutely not.  We simply report that your IP Address is listed.  The effect that it has on your email is 100% dependent on the recipients who choose to use said blacklist as a spam-filter on their email servers. For instance, if your IP is in the blacklist database and the recipient uses it as a filter; your emails will likely bounce and they won’t accept them.  If your IP is not listed, your mail should be accepted in the majority of cases. This also doesn’t mean the recipient server won’t mark you as “Spam” based on content.  If that’s the case, keep in mind your email was still accepted by the recipient server.

Q: Does inclusion of a blacklist on the MxToolBox Super Tool advocate the use of a blacklist?  
A: Absolutely not.  Again, we are simply here to report the data of the blacklist databases.  For blacklists that have a bad reputation for the listing criteria and/or delisting protocol, the problem is not that MxToolBox reports the data; we are here to help alert you.  The problem is the organizations that choose to use said Blacklists as a tool despite their [the blacklists] poor reputations.  We’re here to help you understand that and to make recommendations on how to solve the problems!

A good example is the NOMOREFUNN Blacklist whose website is currently down.  We are aware of the NOMOREFUNN site issue; However, their database is still returning positive results and we will continue to provide those results as long as they are active.

The number one thing about which you need to be concerned is whether or not there is any effect on your outbound mail delivery.  If you are getting bounced or returned messages or your recipients are not getting your messages, then you should be concerned that you have a bigger problem at hand.  Most blacklists can be contacted for removal once you’re cleared up any issues in your network.

Spam and Virus ProtectionEmail hostingGoogle AppsRegardless of what is causing the problem, MxToolBox can offer you a solution that includes Spam & Virus Protection with Outbound Blacklist Managment. If you run your own email server, we can offer you Emergency Mail. If you are hosted and are looking for a bigger, better and more secure environment, we can provide Email Hosting, MxToolBox Supported Google Apps for Business & Microsoft Office 365. No matter which service you choose, MxToolBox is going to take care of your email.

Please feel free to contact our Customer Care Team by emailing or simply call 1-866-MxToolBox (698-6652) with any questions or to learn how you can put the Blacklist issue behind you forever!


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Copyright 2012 MxToolbox Inc. 12710 Research Blvd. Austin, TX 78759




February Newsletter – MxToolbox – A Customer Service Company That Just Happens To Do Email



Why do businesses choose MxToolBox vs. other email solution providers?

Most people come to to use our free tools and to get a better understanding about blacklists and why their company may be on one. The vast majority of those visitors to our website actually buy services from us because we end up knowing more about why they are experiencing problems than their current provider does.

We know that there are many different email and web security options available in the market today but we are committed to being the very best. To prove that, we routinely go above and beyond what many of our competitors are willing to do.

Let us wow you with our “Top 5 Reasons” why you would be crazy to let anyone other than MxToolBox handle your company’s email:

  1. No one provides Outbound-reputation protection against blacklists like MxToolBox does. Over half the people that hit our site already have another Spam-Service provider and/or existing Hardware and Software and yet they still have problems.
  2. No other company provides Email Hosting & Collaboration Suites, Email Security, Email Continuity, Web Security and Server/MailFlow Monitoring– ALL from one source! 
  3. We don’t believe that spam-filtering is all you need… We build inbound-spam protection which includes inbound message continuity with web access and outbound blacklist protection, with no hardware or software – All the protection your company needs is our Total Perimeter Security!
  4. We know all providers are different. That is why we have the best breed of solutions to meet and exceed your company’s requirements. 
  5. We have the SuperTool that brought you here – Why would you go anywhere else?  Plus – we have a Rock-Star Customer Support Team – Highly Available and you can understand us!

 Not to mention we give you a 30-day no-risk, no obligation trial on any of our services.  Please give us a call today at 866-MXTOOLBOX (866-698-6652) or email us at to fix your email headaches for good!


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Copyright 2011 MxToolbox Inc. 12710 Research Blvd. Austin, TX 78759


January Newsletter – New Year’s Resolutions for Email and Network Infrastructure




In the spirit of our “Top Holiday Email Related Tools”, we thought we would start another list each January as our Resolution List.  However, this list won’t be your typical list that includes “drink less soda” or “run a marathon” (all good things!), but will be more along the lines of what you can do to further protect your Email and Network Infrastructure.

Open Relay / Lock Down
In the past it wasn’t such a big deal to have your server as an open relay, but these days even having it open for a few days will more than likely invite spammers to infiltrate your network. An open relay is when an SMTP server is configured to accept anonymous connections to your servers’ IP Address or allow anonymous servers to relay off your server. If you continue to operate with your server as an Open Relay, your server will more than likely end up on a Blacklist which will cause outbound delivery issues.

To ensure that your mail server is not an Open Relay, we recommend only allowing email delivery on your public IP address for email addresses you own. If you have people outside of your network that need SMTP service, employ VPN, SMTP Authentication, or have them use a 3rd party SMTP server.

Another step that we recommended is to block outbound port 25 traffic only to your email server. To do this, simply make a rule on your firewall that stops outbound port 25 connections. Make a single exception for your email server. Lastly, we highly recommend keeping your server secure and running Anti-Virus (don’t forget to run updates!).

Web Security – Locks on the doors, but not the windows?
Now that you have secured your network by closing that pesky Open Relay, you have essentially locked all the doors into your network.  But have you left a window open?  Online threats have shifted their attention from launching attacks through email systems and have begun targeting web browsers as an often unguarded entryway into your infrastructure.

The firewall that protects your business network is configured to stop connections that originate from the Internet. However connections that originate from within your network are automatically granted access. Without this ability your employees would not be able to access any online resources outside of your network. One of the greatest security concerns on the Internet today is malware. This malicious software is often distributed via web pages and is designed to infiltrate a computer system without the owner’s knowledge or consent. Currently 85% of dangerous web activity is attributed to malware which makes proactive
Web Security a necessity for every business. The most critical role of Web Security is to prevent malicious code from being brought in to the network; however, it can also be used to control access and generate reporting on your web usage if desired.

Blacklist Protection
One of the most common security challenges for companies is keeping their organization’s email off of Blacklists. When your company gets Blacklisted it will cause major trouble for your business and it will slow down your communication with current customers, prospects and in general the outside world. Email communication is a critical and profit dependent function of any business and this type of communication interruption is both time consuming, costly and completely 100% avoidable.

If you find that your company’s IP has been Blacklisted, what can you do? Well that is where MxToolBox can help! With Email Service through MxToolBox you won’t have to worry about Blacklists. Our highly trained IT professionals will not only help you find the root cause and eliminate your current Blacklist problems, but we can proactively implement solutions to keep your system protected and secure.  

We hope that you are able to check off most of what we have covered. If you haven’t and you have further questions or need further assistance, please contact us at (866)-698-6652 or and we’ll be happy to help!

Even if your company has not had its productivity hampered by any of the issues described above, now would be an ideal time to review what our Total Security Package which offers top-shelf Spam and Virus, Blacklist Protection and Web Security can do to further insulate and protect your company. With MxToolbox you can rest assured that  your company’s email and web browsing is safe and secure.   

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Copyright 2011 MxToolbox Inc. 12710 Research Blvd. Austin, TX 78759




December Newsletter – We Asked and Our Customers Shared! MxWatch Customer Testimonials


We understand that testimonials from happy clients are an important part of any service business’s website, lending trustworthiness and experience to a business. We have invested years of research and development into improving the tools on our website. In the last few years, we have specifically aimed to improve the Monitoring capabilities and Monitoring services. Here’s what some of our clients are saying about our MxWatch Monitoring!

Brian Tucket, @BrianTuckerSN

@MXToolBox Thank you for the quick response! You guys rock! Love the help you give us! David Beecher, Digital Messaging Solutions

Very much appreciate your help and the tools provided by MXToolbox. Your system provides our team with excellent notification and valuable insight into RBL issues. You have saved us a lot of time and effort.
Lisa McQueen, H&H Homes
I was researching an email problem when I stumbled upon Mxtoolbox.  I subsequently subscribed to the monitoring so I would be aware of when or if we were blacklisted without looking and notified if there was a problem with our smtp gateway.
Patrick Consolati, Winstanley Partners
MxToolbox is an irreplaceable tool for keeping our email customers happy. Without it we would be completely lost.
I write this mainly to show what we do and the importance MxToolbox has to us. In fact my life was not being easy in the last year, in fact, I’m still living in hell. First of all, I want to say that the attention that MXTB has/was giving to my solicitation/critics is amazing. And I say this not (because) MXTB are doing what I asked for, but and most important, by the fact that it prove that very thing that Chad and Brendan told (me) is REALLY TRUE. I really appreciate this. 
Chad Brinkley, @chatbot2048

@MXToolBox want to give a shout to Brendan for some awesome customer service this morning. Thank you very much! Jesper Flindt, MikkelsenMedia

I chose to work with MxWatch as I had a lot of IP’s I wanted to make sure were not blacklisted. MxToolBox supplies excellent service & support as well as an easy-to-work-with system. I would recommend this tool to everyone.

We’d like to thank our customers for taking the time to share their thoughts with us. If you would like to learn more about MxWatch (Server Monitoring), please give us a call at 866-MXTOOLBOX or sign up for your own MxWatch Monitoring account now!


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Copyright 2011 MxToolbox Inc. 12710 Research Blvd. Austin, TX 78759




November Newsletter – Third Time is the Charm! Welcome to the Third Edition of our Top Holiday Email Related Tools


At MxToolBox, we use many email tools on a daily basis and sometimes we forget to share the wealth.  We asked everyone in the office to give us their favorite Email related tool.  We’ve done this for two years now, so you may want to check out the 2009 & 2010 results as well.  Here’s the list!
Keep in mind that this list is not in any particular order but is just a sampling of our favorites. If you have any tools in mind that we missed, please let us know!
  1. Mailflow Monitoring – Last year we recommended our Server Monitoring to help take the guessing out of server management. Earlier this year we released our Mailflow monitoring which is design to test your server end-to-end to detect problems that most monitoring services miss. We understand that even short email delays can be costly for your business. Our solution provides complete mail flow visibility by detecting issues with inbound or outbound mailflow.
  2. Send Test Email– This tool is from Wormly and is pretty cool. All you have to do is enter your SMTP server and then a sender and recipient. Then just hit the button and it shows you the SMTP conversation.
  3. Traceroute– We’ve had this one on our list for a couple of years now. This year, we’ve found a new tool that does all the work for you! Traceroute tracks the path that a packet takes from your computer to a destination address. A traceroute also shows how many times your packets are being rebroadcast by other servers until it gets to the final destination.
  4. DNS Check – This tool can help troubleshoot potential problems with your domain, web and DNS. It checks each step in the chain that links hostname to IP address. If it finds a problem, it flags for attention.
  5. Sender Score – This tool is a free email reputation service that can give an indication of the trustworthiness of an email source. The list is complied by Return Path and may help you pinpoint if you have a sender reputation problem.
  6. Quick Zone Check – Performs a series of checks on your name servers and email servers. Returns WHOis, MX, Name Server and more info all in one place.
  7. Blacklist Monitoring & Delisting Support – The MxToolBox Blacklist Tool checks your IP against a list of over 150 Real Time Blacklists. We also now offer Blacklist monitoring and Delisting Support.

    Last but not least, we would like to include three of our own Free Tools which help make troubleshooting, diagnosing, and monitoring your email easier. We have been providing our free tools since 2003 and we are proud to continue giving back to the email community.

  8. Blacklist Lookup– The MxToolBox Blacklist Tool checks your IP against a list of over 150 Real Time Blacklists. If your mail server has been blacklisted, some email you send may not be delivered.
  9. – MxToolBox Ping is one of the Free Tools provided by MxToolBox to help you determine if Inbound and Outbound mail flow is working. Simply send an email from your network to and the tool will look at the email headers of your message and send you a notification back immediately. Please note that the subject and body do not matter. The response email will include several helpful troubleshooting tools including your Outbound IP, server hops, any transaction times or delays and it can help trace the route your email is taking to discover any outbound gateways you might be using.
  10. MxToolBox Free Tools – We mentioned this tool last year but once again we have made some updates! All the familiar tools you are using on a daily basis are still there but we have added Ping, Trace, SOA, TCP, HTTP and HTTPS. These have also been added to our Server Monitoring so you can monitor those commands as well.

As always we are open to your tool suggestions as well. Please feel free to share!

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Copyright 2011 MxToolbox Inc. 12710 Research Blvd. Austin, TX 78759




October Newsletter – Demystifying Email Bounce Backs and Errors


Last month we started a series of posts on our Blog covering Email Bounce Backs & Errors. These errors can be incredibly confusing and misleading, so we wanted to try and demystify these problems. Read on for a few of the most recent articles that cover a wide spectrum of email problems related to bounce backs and associated error messages.


Non-Delivery Report (NDR) Spam or Backscatter Spam

Monday, September 19th, 2011

In our continuing blog series about bounce backs and error codes we wanted to talk about NDR Spam or Backscatter Spam. As we all know, spammers are tricky devils and they spend the majority of their time learning to adapt and circumvent email defense systems. One example that demonstrates the type of adaptability that Email Security professionals have to deal with is Backscatter spam. As an operator of a legitimate email server […]


Posted in Bounce Backs, Knowledgebase| 1 Comment »

Bounce Backs: Denied For Spam, Message Rejected, Spam Source Blocked, What Does it Mean?

Wednesday, September 14th, 2011

Have you ever received a bounce back that refers to your message as being blocked because it was considered spam? While the actual language of the bounce back or error message may vary if the error code is a 500 error, that does mean the message could not be delivered to the recipient (400/500 Email Bounce Back Errors Explained). In this particular case, we are referring to bounce backs that reference messages as being denied due to spam or IP reputation […]


Posted in Bounce Backs, Knowledgebase | 1 Comment »

400/500 Email Bounce Back Errors Explained

Tuesday, August 30th, 2011

Bounce backs and error codes might look like they need to be deciphered with a secret decoder ring. We are going to try here to shed some light on them so you can crack them open and extract the goodness within. So let’s work together to understand the the two most common types of bounce backs. When a bounce back message is generated, the mail server that issued it is attempting to let you know there was a problem with sending the message and give you some information so you have an idea of what […]


Posted in Bounce Backs | 1 Comment »

550-”5.7.1 Message rejected as spam by Content Filtering.” – Intelligent Mail Filtering with Exchange

Friday, August 19th, 2011

This is an error that our customers run into pretty often here are MxToolBox so we thought we would help explain the cause and provide some solutions to remedy it. By default Microsoft either installs/or recommends that the Intelligent Message Filtering (IMF) service be enabled on all installations of […]


Posted in Bounce Backs, Knowledgebase | 1 Comment »

‘4.3.1 Insufficient system resources’ – Back Pressure Feature Exchange 2007

Monday, May 9th, 2011

We see this type of error pretty often here at MxToolbox and so we wanted to post about it here. Customers Exchange servers can mistakenly react to normal mail flow and cause a disruption in service. The error that is posed is ‘4.3.1 Insufficient system resources’ […]


Posted in Bounce Backs, Knowledgebase | Edit | 1 Comment »

How to Read Email Bounce Backs and Errors

Thursday, May 5th, 2011

To kick off our series on demystifying and understanding email bounce backs and errors, we thought it would benefit everyone to go over how to read a bounce back. Some bounce backs are very cryptic and full of codes and numbers. How are you supposed to figure it out? Let’s break down a typical bounce back […]


Posted in Bounce Backs, Knowledgebase | 2 Comments »


We have been supporting our Business Email Products (Spam & Virus Filtering, Emergency Mail and Hosted Email) for years and we take pride in sharing all the knowledge we can with our customers and non-customers. We hope that these articles help you maximize the impact of your efforts by utilizing MxToolBox, our Free Tools, Server Monitoring and Business Email Products to their fullest potential.

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Copyright 2011 MxToolbox Inc. 12710 Research Blvd. Austin, TX 78759


September Newsletter – MailFlow Monitoring – Giving you the Power to Save the Day!


Most people can relate to that, “I just sent you an email, do you have it YET?” experience.  Most monitors only detect when your email is down completely.  MailFlow Monitoring from MxToolBox will tell you when your server (or service provider) is SLOW.  And, you can see those trends over time.

90 Day View

If you have ever found out that your mail server was down from one of your users, and you are the System Administrator, you know that can be kind of embarrassing, not to mention stressful. MailFlow Monitoring was built specifically by our Engineers to go beyond just monitoring static SMTP availability, so you can know right away when there is an issue. It provides real-time daily, weekly or monthly statistics by monitoring the status of all mail in and out of your server. With this information you can really start to build a true picture of the Up/Down status and performance of your mail server. Plus the system can help you identify any issues with intermittent delays so you can address the problems before they escalate.

How does it work?
The MailFlow Monitor tests the full availability and performance of an SMTP server by sending a test message every five minutes to a predetermined mailbox on your domain. Once the message is injected into your server it obeys the mail hops or set routes and then your mail server auto-replies or forwards the message back to us. Once we receive the reply we automatically graph all the data for you showing the high and low response times and how long it took mail to pass in and out of your server. This graphical data can be sorted by multiple time periods, i.e. last 7 days, 30, days, etc.

7 Day View

We built this service so we could monitor the status of our own many mail servers!  When we really looked at our own needs we didn’t feel that any of the current available monitoring services in the market could tackle this request in an efficient and cool way. After seeing how valuable the end result was in managing our own infrastructure, we realized that we couldn’t keep the tool all to ourselves, so we made it available to everyone!

To get the power to save the day, you need to check out our Basic and Professional Monitoring Products.

*Note that that MailFlow Monitoring is not eligible with a Free Monitor account.

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Copyright 2011 MxToolbox Inc. 12710 Research Blvd. Austin, TX 78759