The service “imap” up and down every few minutes

I'm facing similar problem with the IMAP services, I'm using a dedicated server with 80+ domains, with many users, the error I got is: TCP Transaction Log: Failed to read from socket: << TCP Transaction Log: Failed to read from socket: imap: ** [TCP Transaction Log: Failed to read from socket: != * OK] : Died ----------------- I did a few fixes that I got from this forum but none worked, the services is up for a few minutes then it goes down... I got a license from a third party providers but their support is very veeery limited, seems to me that they have no clue on what the actual problem is. I need to find a fix for this problem.