If you are having problems with your email server; there could be any number of issues which could be at the root of the problem. However, most e-mail issues fall under 3 main categories: Email Server Problems, Spam Blacklist Entries, and 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 e-mail server.
This service will let you type in your domain – this is the part after the @ in email@example.com. For this example we are going to use bluetreehost.com.
Type the domain name in the web page, make sure “maximum details” are checked, and then click “Check”.
This will load a page which transverses your DNS for that domain, and ultimately try to connect to the mail server. A successful mail server entry will look like this:
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. When sending an email, if you get a rejection mail back that states you are on a spam blacklist, then this is the cause of your email woes.
Many email servers use Realtime Blackhole List (RBL) servers to cut down spam drastically. One of the most popular services is SpamCop.
Use OpenRBL.org to check to see if your domain has been blacklisted.
Enter your site into the OpenRBL IP/Domain box:
Press enter to update the page.
Then click the green button which says “Openrbl JS Client”
Below is a sample result:
Click on each blacklist server to see a more detailed example of it’s response. In the above example – when you click on APEWS RBL server it states that this is a false positive and gives you links to do further testing.
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 e-mail administrator!