I cannot find this addressed specifically anywhere and i have asked the specific vendors of the products as well and usually get nowhere.  Because the problem is random and not specific to any one user but seems to affect everyone at some point and also seems to eventually resolve itself, it is hard to get anyone to take responsibility for it.  But we never had the issue before on normal outlook and it only began afeter we went to exchange 2013 server email.

While i am not saying for sure it is any one specific program, we all use the same ones and all have the same issues eventually.  Also all have found that the same "fix" works.  Turn off Malwarebytes.  Instantly connection is made and all email that has backed up sometimes for hours will begin to flow in both directions.

I would rather not remove this software aas it has protected us quite well foer a long time but the tech Support there is not willing to admit anything and I cannot figure out what files to exclude in order to get the email to work.  The articles i have located re Microsoft Forefront etc also mention excluding folders but again i am not able to find any specific folders with regard to exchange 2013.

Any help or advice appreciated