Outlook 2011 for Mac (version 14.2.5)

Hello,

I have two questions :

Question  1 :

My inbox in Outlook 2011 for Mac (14.2.5) is refreshing every few minutes, meaning my all emails disappear at once and they are re-appearing, being downloaded again, one by one. This happen maybe 20 times per hour (how frustrating it is...)
What is the option(s) I need to adjust in my settings ?

Question 2:

I cannot send anymore pictures above 1.5MB (and I could send some before). And for smaller pictures, it takes a lot of time....
What is the option(s) I need to adjust in my settings ?

Are the above issues a general problem with Outlook and Mac or is this an issue with my Imac (bought few months ago) ?

Thanks.

TintinMilou987