Hi,
My outlook for mac crashed this morning, I have had error messages the last few days but the problem didn't sort it's self out this morning.  I have tried to rebuild the identity but receive the following error message

idStep 1 of 5: Scanning…
Your database could not be rebuilt. [-20997]

I have taken a copy of the identity and tried to rebuild this but I receive the same error message.  Why is outlook for mac such an inferior product? I've had issues over the years with Entourage and Outlook 2008 as well.

Feeling very frustracted