Windows 7 Backup Service - Running account change

I want to run my backup service under a different user account for security reasons (My personal folder restricts access to only my user account).

I change the run service as property, but after I do, the service will not start, with the following error;

"Error 1297: A privilege that the serive requires to function properly does not exist in the service account Configuration."

I tried the secpol.msc, and added my user account to the backup operators group (already an Admin) andrun as a service, but it still does not want to start.

Can anyone tell me what privs my account needs to run this service?

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