trying to format my pc with xp copy

Right i had xp installed at a retailers when pc was originally bought.i then deleted win32(don't ask) and had to get help to format.the guy who formatted it then reinstalled xp using a copy of the original disc,when asked for a serial no, i could not find mine and phoned my friend who gave me a number over the phone.all is now well!..... one year later, i have auto updates installed and microsoft installed an update that knew my xp was pirate i also cannot use microsoft websites to download things( planes for flight sim etc) as they run a quick search and discover xp not real. so what i want to know is, i have since found my serial no on the side of my hard drive and want to know if i format my pc can i use the dodgy disc again but then enter my unique serial number to install it properly. i want to format as since this began i have deleted things ,my printer for example but obviously not all parts as when i try to reinstall not allowed, also other things, . could i also ask if formatting is easy i am a relative amateur but feel i can follow instructions well, this is really getting to me can someone please help,cheers Coldo

 

if you can get a copy of xp, just put it in your cd/dvd drive then re-boot and then follow the on screen instuctions, do a complete format, set-up will prompt you for the serial, its quite easy - any problems and we are here to help,
good luck

 

It should work fine. As long as it is the same version of XP. You can't use a key from XP home for XP pro.