You could make a migrate.inf, and add that to your install media. e.g. [Version] Signature = "$Windows NT$" [Addreg] HKLM,"SYSTEM\MountedDevices","\DosDevices\C:",0x00030001,\ CC,CC,CC,CC,00,7E,00,00,00,00,00,00 ;where CCCCCCCC is the disk sig, bytes 440 to 443 of mbr ;00,7E,00,00,00,00 is 32,256 = 63x512