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Best Exim Tutorials and cPanel Email Tutorials

Exim is one of the best Mail servers around for LInux and Unix operating systems. And it’s also the default Mail server for cPanel/WHM control panel. cPanelTips Exim Tutorials try to explain the exim way of working and brings solutions for common exim problems.

At the same time, our Exim Tutorials will teach you how to improve Exim performance and increase Exim Security.

You will also find general Email tutorials for cPanel servers.

List all IMAP and POP email accounts on a cPanel server

This is a quick hack to list all IMAP and POP email accounts on a cPanel server, from all the existing domains. If you ever need to list all your mail boxes that are currently working with the IMAP or POP3 protocol, then run this scripts: To get all your IMAP mailboxes cat /var/log/maillog | zcat /var/log/maillog-* |…

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How to fix: Warning: fd limit (ulimit -n) is lower than required under max. load

This happened on a recent cPanel server. Dovecot was showing this error message while restarting the service: Starting Dovecot Imap: Warning: fd limit (ulimit -n) is lower than required under max. load The fix was quick and easy. You just need to reconfigure dovecot and rise the file descriptor limits. Edit dovecot configuration file: nano -w /etc/sysconfig/dovecot Add this…

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How to Repair eximstats on cPanel/WHM

Today you will learn how to repair eximstats on cPanel. Sometimes Eximstats, the cPanel daemon in charge of generate stats for email usage, stops working. In order to get your email stats working again, we will have to delete the current MySQL tables and re-create the stats again. How can I repair eximstats on cPanel? At the logs,…

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Your access to this mail system has been rejected due to the sending MTA’s poor reputation error

Sometimes when you are sending email to remote hosts you can get this kind of error: Your access to this mail system has been rejected due to the sending MTA’s poor reputation What is the cause of “Rejected due to the sending MTA’s poor reputation” error? It’s a pretty common error when your IP address has been sending SPAM…

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How to Add Barracuda RBL to Exim on cPanel

One of the best ways to stop incoming SPAM on cPanel servers is to use the RBL feature that Exim includes on its configuration. By default, cPanel servers comes with two pre-defined blacklists: RBL: bl.spamcop.net RBL: zen.spamhaus.org Those are disabled by default on standart cPanel installations. However, even if you enable both blacklists, I’m pretty sure you will…

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Dropped: too many syntax or protocol errors Fix

Today one of my customers reported an error while sending emails from Outlook / Outlook Express, after investigating Exim logs I found this: Dropped: too many syntax or protocol errors SMTP connection from [90.29.110.197]:63138 (TCP/IP connection count = 3) SMTP call from (PEMVAR54) [90.29.110.197]:63138 dropped: too many syntax or protocol errors (last command was “RCPT TO: <‘someadress@hotmail.com’>”) This…

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Error 421: too many concurrent smtp connections

On high traffic email servers you may see this kind of errors, it’s very normal in some situations when your users use lot of email. It basically means that there are a lot of open SMTP connections (incoming and/or outgoing). The exact error message may be something like: 421 Too many concurrent SMTP connections from this IP address; please…

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