the problem I have is I unknowingly purchased an illegal vista disc from ebay. It was ok for a month using the product key then microsoft declared it was illegal. I have now bought a legal windows7 ultimate but i'm unable to install. The computer boots up ok showing illegal vista disc and I'm unable to install my new legal windows 7 ultimate. What I would like to know is that if I change my hard drive dric will this solve my problem??
Golfjack

Back up your documents to cd/dvd or external drive before doing anything else. Format your Hard drive and then you should be able to install Vist as long as you use the key supplied with the legal disk. This is the easiest way but be prepared to install all your other applications and drivers and any service packs and updates afterwards.

Before doing anything that drastic, try activating by phone. When it fails you will be connected to a MS rep. Tell them what happened and he/she may be able to activate your current Vista install using the new legal key.

To activate Windows Vista over the telephone, follow these steps:

1. Click Start
2. Click System properties on the toolbar, and then click Click here to activate Windows now in the Windows activation area. If you are prompted for an administrator password or for a confirmation, type the password, or click Continue.
3. The Windows Activation Wizard starts.
4. Click Use the automated telephone system in the Windows Activation Wizard.

Worth trying before going through a reinstall.

I have decided to replace my harddrive can you forsee any problems ?.I have already backed up my details on disc. Will the new harddrive format automatically? golfjack

Follow these instructions by Brink: Clean install Windows 7