I have the same problem. I successfully connected Outlook Express to my email server (both wth POP3 and IMAP) but I can't to that with OTRS 2.3.4 on Windows. I always get the error message

 

[Wed Jun 17 17:32:07 2009][Error][Kernel::System::MailAccount::IMAP::Fetch][72] IMAP: Can't connect to <server address>

 

In my log <server address> is the correct IP address of the server, the same used in Outlook Express.

 

What I'm missing?