Smokem 0 Newbie Poster

I have 2 clients that are reporting a strange issue. 1 is running outlook the other outlook express.

Within the last 24 hours both systems have starting prompting for them to log into the Microsoft Network when they do a send and receive, if they click cancel they get and error and can't receive email.

Both are running IMAP for our email, 2 different companies and locations.

I've looked every where and can't find a solution. If they reboot send/receive works first time, but subsequent tries fail. If you make changes same thing.

Help...