mail server problems

[Lenvanessen]

Hello,

I have Postfix smtp installed on my server en it worked fine until now.
Ik can't connect to my server with any settings, i've tried everything. Rebooting the system, rebooting the service.

Does anyone has suggestions, maybe another service that handels all smtp traffic on my server?

I'm currently running Plesk 10.2.

Also why can't any mail client autodetect the correct settings?

Thanks!