Contents of .reg-File:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate]
"WUServer"="http://192.168.2.23:8530"
"WUStatusServer"="http://192.168.2.23"
"UpdateServiceUrlAlternate"=""

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate\AU]
"UseWUServer"=dword:00000001