cannot send out mail ...............

[perag]

I had no problem till I migrated to a new server account on which Plesk is installed. I could send and receive mails from my earlier facility which was not having Plesk. Now I cannot send out mails if the smtp domain set is on the server where plesk is in use. The moment I change the smtp domain to one which is on the old server without plesk my mails go out. What could this be ????? I have also tried and set an alternate smtp as 25025 instead of the default port 25 but it did not help.
Someone Plz help fast.................................

 

[webhilfe]

is qmail running?
Your OS?
look at the logs, post error