A visitor to our OutlookForums had this question about Outlook 2011 for Mac:
When I attach files to email, it is automatically compressed (zip'ed). Is there any way I can turn this off? ...and where? ...I have looked everywhere and I can't find it.
This is the result of importing from Entourage 2008.
When you import your Entourage settings, some preferences and settings are transferred and zip compression is one of these settings. Unfortunately, at this time there is no way to change the settings in Outlook.
The solution: You need to save your data and create a new identity then import the data.