I have searched for two days trying to figure out why I keep getting this error. I am using vpopmail 5.4.30 and mysql 5.0.77-4 on CentOS 5.4
I can reproduce the error by restarting the mysql server. The only way to make it work after restarting mysql is to also restart authdaemond. I did find some info on the mailing list that says: To describe the problem: when you run vpopmail in MySQL mode, with courier-authdaemond and MySQL v5.0 or later, you will find that for the first 8 hours, everything works just fine, but after 8 hours, nobody will be able to authenticate to the email server and you will see "MySQL server has gone away" errors in the maillog. The cause of the problem is that in MySQL 5.0 (and probably some 4.1 releases), MySQL implements a new timeout definition for connections, a timeout that ignores traffic. This timeout will shut down the socket thread from the MySQL side. The problem is that the client (vchkpw and friends) do not know/understand about this timeout and socket termination so they continue on in ignorate bliss until they try to send to the socket and find that it's no longer valid - literally "the server has gone away". And a patch is offered but the version of vpop that I am running already has that patch installed. Anyone else have any ideas? Disclaimer For Citizens National Bank "The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon this information by persons or entities other than the intended recipient is prohibited. If you received this message in error, please contact the sender and delete the material from all computers." This original email was sent to the internet for delivery at 13 May 2010 10:37:55 -0400 !DSPAM:4bec0ec432711330214813!