I have been happily running Zimbra Collaboration Suite 6.0.6 GA Open Source Edition for several months now, and recently upgraded to 18.104.22.168 when it became available. I am running ZCS on my CentOS Linux 5.5 i386 home server and haven't had any problems with it (save for one minor issue) up until now.
I was using the Webmail interface just fine until all of a sudden I received an error last week when I tried to send an e-mail. The error reads simply, "Cannot connect to server," and there is nothing in the pane that appears after I click "Show Details."
I have restarted the server many times and have tried from different computers and by entering different e-mail addresses, subjects, and messages in the Webmail interface, but still get the same error every time.
Unfortunately I don't know enough about Zimbra to be able to troubleshoot / resolve this problem, so I thought I'd ask about it here in the forums.
I appreciate any and all assistance given and look forward to hearing from the community. I really like ZCS and applaud the Zimbra developers for creating such an excellent product.
Thanks in advance!