By runonce or setupcomplete.cmd but it really is a useless program, it would be better to block the install by WU: Code: Windows Registry Editor Version 5.00 [HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\MRT] "DontOfferThroughWUAU"=dword:00000001 You can load the reghive and change it on a mounted wim. A dirty trick is to unpack MRT using 7zip and manually copy the content to "c:\windows\system32".