I am migrating my mailserver from windows server 2003 (64 bit) to server 2012 R2. Webmail is already up and running on https (iis 8), but unfortunately I can not connect to imap service on port 993. It was perfectly working on 2003 (smarter mail v12). I transferred the configurations to my 2012 server, changed all ip-configurations accordingly and created a new certificate. I get no information in the logfiles (all log levels set to 'detailed'). Disabling the firewall doesn't change anything. I can connect to port 993 by telnet and portqry.exe. I tried both smartermail v12 and v13.
Are there any special settings in 2012 R2 that I missed?