I have an old XP machine. An Acer Aspire. I put Win7 Ultimate on it but it hasn't taken. Always gives me an error message and asks for the install disk again - which was a USB stick - but when i provide it nothing changes. So I need to get it off and start again. I have 3 physical disks divided into 4 virtual disks. Disk manager describes them like this: Disk 0: 20G Fat32 System. That's C drive Disk 1: 75G NTFS Active That's D drive Disk 2: 98G NTFS Active That's E drive 135G NTFS Boot That's G drive. WinXP is installed on the G: boot drive. I had 20G free on the D drive and I just let Win7 find it and install itself there. All the advice I find on the web says delete the partition of the Win7 OS you want to remove. Well I don't want to delete that partition because it has gigabytes of data already existing before Win7 installed itself there. So how do I go about it? Is it simply a matter of deleting the Windows Folder and editing the boot manager text file? There was another old XP OS on that drive used before I installed this one on G: and win7 has renamed it windows.old. That's fine. There's also a Program.data folder that seems to have been made at the time of this win7 install. That should go too? There's also a Program Files folder that doesn't seem to have been made by Win7, because of folder dates. I don't know about it. Is it part of that ancient XP install or is it part of the new Win7 install? Either way it can go. I don't need that ancient install, it is just rubbish now. What should I do?