How to Reset WSUS's Client SID
Needed to reset WSUS's Client SID for Colleagues' Computer.
Update
That might be because it was built by a Backup Image.
net stop wuauserv
reg Delete HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate /v SusClientId /f
reg Delete HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate /v SusClientIDValidation /f
net start wuauserv
wuauclt.exe /resetauthorization /detectnow
reg Delete HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate /v PingID /f
reg Delete HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate /v AccountDomainSid /f
reg Delete HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate /v SusClientId /f
reg Delete HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate /v SusClientIDValidation /f
net start wuauserv
wuauclt.exe /resetauthorization /detectnow
Reference
Update