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Exactly how are you wanting to completely remove Office 365? I would first need to know how your setup your account to provide help. Did you configure a Connected account through OWA? You might also want to explore support through mobileme if that is where you are encountering the sync issues, since I do not have a great deal of familiarity with that product.
I want to remove from Outlook whatever Office 365 added to it - mailbox, "suggested contacts", calendar, etc. I can not delete the email account that was created - Outlook returns a message that I can not delete the email account because it is the primary account.
Simply said, I want to uninstall Office 365 from Outlook 2010 64-bit. How do I do that?
You (MSFT) need not be concerned with MobileMe.
Again, I cannot speak with much authority without understanding more about your configuration for example if you have multiple exchange accounts in Outlook or other accounts of other types etc. If Outlook is referencing the default message store being set to the Office 365 account as you are indicating these steps should be able to resolve the issue. Go to: File > Account Settings > Account Settings... > tab Data Files and set another account as Defult. Once this is done you should be able to delete the account. Another method could be to create a new Outlook profile and delete the one containing Office 365.
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