If you need to know where your client machine points to for it’s windows updates via registry, follow below instructions.
Modifying the Windows registry can be dangerous. Incorrectly modifying the registry can destroy your operating system, applications or data. I therefore highly recommend that you perform a full system backup prior to attempting any of the techniques on this website.
1) Launch registry
2) Browse to HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate
3) The Windows Update server name can be located within the registry name WUServer