outlook 2011 for mac cannot connect to exchange 2010

I need your help in figuring out this challenge: Outlook 2011 for mac cannot anymore connect to Exchange 2010.

It used to work in the past but 2 weeks ago outlook 2011 for mac stopped receiving mails. 

I have a lot of experience in the Windows environment but no experience in the MAC world.

The boss has the only mac in the shop, now Outlook is not syncing anymore and I have to fix it :)

I uninstalled and then reinstalled Office 2011 - did not fixed the issue.

Testexchangeconnectivity - works, no problem here - the user and password are ok; his connection from iPhone still works.

i turned on logging from outlook but I can't find any error, I could not find nothing useful there also ...and this is why i'm asking for your help.

this is the print screen of what do I get, no connection: on the server side I can see that the user managed to log on but nothing happens.

Please advise,

Thank you,

Alex