cmd has been runned without of admins rights - copy DELL.XRM-MS (certificate) to the root of C:\ - run cmd as Administrator : Code: cscript %windir%\system32\SLMGR.VBS -ILC C:\DELL.XRM-MS cscript %windir%\system32\SLMGR.VBS -IPK "replace with your OEM:SLP key" SLMGR.VBS -XPR