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At some point, before Whitman College moved to Gmail, there was an account with a Google service using your @whitman.edu email address. This could have been anything like YouTube or some other Google service. When Whitman started using Gmail services, the previously created account was renamed to this GTempAccount in order for your @whitman.edu account to exist as an email account. In order to resolve this issue, you will need to sign into this GTempAccount with the password you setup for it originally. This was sometime ago so it may be an old password you no longer use or recall.
The warnings you've been receiving is These warnings are related to some an app or service that had permission to your account, but no longer does.
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