Professional Email Services

How to Troubleshoot Email Server Problems

If you are having problems with your email server there are a few could be any number of issues which could be at the root of the problem. However, most email issues fall under 3 main categories:

    1.Email Server Problems
    2.Spam Blacklist Entries
    3.DNS Problems

1. Email Server Problems

If your mail server is misconfigured or otherwise has system problems, there is not much you are going to be able to do about this. You'll need to contact your system administrator and have them look into the problem. One of the best ways to narrow down a configuration issue is to watch the mail log for errors, usually the problem will be revealed in the logs.

2. DNS Problems

If your domain's DNS has been misconfigured, this can cause a lot of email problems. There is a simple way to check your DNS entries to see if external servers can find your email server. Be sure to check the DNS Records radio button.

DNS Check

This service will let you type in your domain - this is the part after the @ in For this example we are going to use

This will load a page which traverses your DNS for that domain, and ultimately try to connect to the mail server. A successful mail server entry will look like this:

10	5 min	SMTP Test	Blacklist Check
10	5 min	SMTP Test	Blacklist Check
20	5 min	SMTP Test	Blacklist Check
20	5 min	SMTP Test	Blacklist Check
30	5 min	SMTP Test	Blacklist Check

To make sure the server is alive click on the 'SMTP Test' link.

If the SMTP test shows that your email server is an open relay you will almost certainly be blacklisted - see the next section.

If the SMTP test returns anything except 'OK - Reverse DNS matches SMTP Banner' some corresponding servers may not accept your email for delivery.

If you see an exchange like this, your email host is running normally.

Session Transcript:
250 [47 ms]
250 ok [62 ms]
553 sorry, that domain isn't in my list of allowed rcpthosts (#5.7.1) [47 ms]
221 [62 ms]

The 553 error shown above only means that the domain used in the test ( is not handle by and is normal for the purposes of this example.

3. Your server has been DNS Blacklisted

If your server has been sending out spam, maybe even on a different domain, it can cause your IP address to be blacklisted. To check if your IP address is listed, click on the 'Blacklist Check' link.

Tiopan	 	LISTED	
If you see anything but 'OK', you have a problem.

In conclusion, email is a complicated system where anywhere along the line problems can pop up. Some other common email problems involve domains over quota, incorrect email client configuration, and temporary internet issues. Using the above sites should help you narrow down many of the problems your email server may be having and give you a good idea as to which direction you need to investigate further. If you have not been able to track down the problem you are having, send any information you have found to your email administrator!