Entourage MAIL ERROR

[antonioconte]

Hi, I keep getting "Action, could not be completed, MAIL ERROR" on launch in Entourage OSX , And what happens also, is that emails, NEW emails, appear with the star indicating that they are unread, fine, but when I read them, they still have the star. Also, after writing an email, clicking onto SEND does nothing, but using apple enter does?

Any ideas. The only thing I did yesterday is ran software update which indicated to update SECURITY SOFTWARE - so I did - is this linked?

Help!