Outlook 2013 not downloading mails

Outlook 2013 not downloading mails

Hello!

I am using Outlook 2013 which was working fine for half a year with my zoho custom email account. Now it Outlook doesnt downlaod messages anymore. I  also have a hotmail acount and that one works fine and Outlook is donwoading messages frome there.
I recdtnky installed AVG AntiVir, but the download still does not work when I switch AVG off.  
Outlook says connected and no error messages.  

I can send messages though.


Any suggestions?

Edit: When I randomly press the "sync all folders" button it works after approx 10 times....

Thanks!