Depending on the make of the laptop , there might be a 'recovery partition' on his hard drive. On boot, press F8 and this will take him into the BIOS, OR whwn it loads, go into the PROGRAMMES (if its ACER - ACER Management and run the recovery from there. HE WILL lose all data though so make sure he isnt worried about loosing any photos/letters etc. IF he hasnt got a recovery partition, he will need the CD/DVD RECOVERY DISK and insert this into the drive and follow the prompts :-)