Office 2010: Error 1920
When installing or starting Microsoft Office 2010, you receive: Error 1920. Service 'Office Software Protection Platform' (osppsvc) failed to start. Verify that you have sufficient privileges to start system services.
This may occur if certain permissions are too restrictive on the Office Software Protection Platform files under either or both of:
C:\Program Files\Common Files\Microsoft Shared\OfficeSoftwareProtectionPlatform
Also, permissions on the registry key HKCR\AppId may be too restrictive. If the ACL for that key includes a user RESTRICTED with read-only permissions, add the Full Control permission for that user.
Then let the Office 2010 repair/install fail, then start again.