The problem I had was that I was trying to configure more than one Exchange E-Mail account. So I deleted the account from the Evolution settings but the directory still remained in ~/.evolution/mail/exchange. After removing that directory all is working well.
Thanks Arthaey ! That one worked for me, too.
The problem I had was that I was trying to configure more than one Exchange E-Mail account. So I deleted the account from the Evolution settings but the directory still remained in ~/.evolution/ mail/exchange. After removing that directory all is working well.