Pegasus und Strato

Hallo,

ich benutzte Pegasus 4.12a und Strato als Mailserver.

Bisher ging alles reibungslos. Seit kurzem kriege ich beim versenden (empfang geht noch) von mails folgende Fehlermeldung:
\“The SMTP or POP3 host to which you are attempting to connect (post.strato.de) has returned a response which is not valid according to the protocol in use. This problem may indicate that the server uses a later or earlier protocol revision which is not compatible with Pegasus Mail, that the server is not the right type of server or is misconfigured, or that there may be a network error of some kind. You should contact the administrator of the host to which you are trying to connect for further assistance.\“

Hat jemand eine Ahnung was falsch sein könnte?

Bereits im voraus vielen Dank

Andreas