'Log on as a batch job' permission is required to run a backup scheduled task.
On Domain Controllers, the Local Security Policy (secpol.msc) cannot be used to configure 'Log on as a batch job' rights for domain account configure to run the backup job. The option is greyed out.
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Use Group Policy Management to configure the setting while logged on to the Domain Controller as a Domain Admin user.
Navigate to:
Group Policy Manager -> Forest: [your_domain] -> Domains -> [your_domain] -> Domain Controllers -> Default Domain Contollers Policy
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Right-click and select Edit... to open the Group Policy Manager Editor.
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Navigate to:
Default Domain Controllers Policy -> Computer Configuration -> Policies -> Windows Settings -> Security Settings -> Local Policies -> User Rights Assignment
Select the 'Log on as a batch job' policy and edit Properties to Add User or Group to the setting.
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