Re-Installing XP on Computer 13:26 23 Sep 05

Can I register my own legal version of Windows XP Pro on a computer that already has Windows XP Pro installed.... or do I have to reinstall from the start?

I bought a second hand computer that already has XP Pro installed. I do not have licence or activation code.

I own my own full version of XP pro and want to install it on this computer

  ventanas 13:47 23 Sep 05

I would wipe any second hand machine as a matter of course, you never know what may be lurking. Use your own XP disc to reformat and reinstall.

  Pooke 13:53 23 Sep 05

If it is retail, which it sounds then you won't have a problem and you can do it.

Glad to see you opened your own thread, as I said if it is OEM then you can't.

What kind of computer is it? You may need additional drivers, try visiting the manufacturers website.


  smudge101 13:54 23 Sep 05

Are you looking for legal guidance or just whether it can be done?
You can install from your XP disk but I don't think it wil be legal unless you have a multi user licence.
Perhaps someone here will give you more detailed info 14:05 23 Sep 05

I only want to install my Windows XP on this single machine. It is not multiuser and I will not be using it on any other computer.

The reason I am asking if I can avoid a complete reinstall is to avoid any issues with drivers etc. The computer is working perfectly.

I was hoping there was some way I could enter my licence number, name etc. without a complete reinstall

  smudge101 14:15 23 Sep 05

There are programs available to change the product code and name etc. A good search on google will show you these.

I second ventanas' opinion that a reinstall is the way to go with a used computer, you never know what nasties are lurking.

XP covers most drivers these days, and you can always see what drivers you have on the machine and make sure you download them to a floppy/cd or usb drive.

And XP doesn't take long to install on a reasonable machine.

  ventanas 15:21 23 Sep 05

As smudge101 has said XP does cover most driver issues, but you can always ask it for a report of any potential problems at the very start of the process, and get hold of anything you need before you start. I also ehco what Pooke has said. If your XP disc is OEM then you cannot use it, if retail no problem at all.

Just make sure that the machine is set to boot first from the cd drive.

  Fruit Bat /\0/\ 17:53 23 Sep 05

Option 1.
Repair XP by install over the top of existing systm

1. Boot the computer using the XP CD. You may need to change the boot order in the system BIOS so the CD boots before the hard drive. Check your system documentation for steps to access the BIOS and change the boot order.

2. When you see the "Welcome To Setup" screen, you will see This portion of the Setup program prepares Microsoft Windows XP to run on your computer:

To setup Windows XP now, press ENTER.

To repair a Windows XP installation using Recovery Console, press R.

To quit Setup without installing Windows XP, press F3.

3. Press Enter to start the Windows Setup.

To setup Windows XP now and Repair Install , press ENTER.

DO NOT choose "To repair a Windows XP installation using the Recovery Console, press R", (you Do Not want to load Recovery Console).

4. Accept the License Agreement and Windows will search for existing Windows installations.

5. Select the XP installation you want to repair from the list and press R to start the repair.

6. Setup will copy the necessary files to the hard drive and reboot.

Do not press any key to boot from CD when the message appears.

Setup will continue as if it were doing a clean install, but your applications and settings will remain intact.

Option 2
Change the number. click here

1. Run regedit and go to: HKey_Local_Machine\Software\Microsoft\WindowsNT\Current Version\WPAEvents on the right double click on "OOBEtimer" and change at least one digit of this value to deactivate windows.

2. Choose run from start menu and type in this command: %systemroot%\system32\oobe\msoobe.exe /a to get the activation screen and go to the second option which is activate by phone.

3. In the new screen choose the option to change product key, and type in the new product key (Corporate one only).

4. Close that window, reboot your system and enter the command in step 2 for the second time to verify your activation you should see "windows is already activated".

To determine the Windows product ID on your computer:

On the task bar, click the Start button.

Right-click My Computer.

On the context menu, click Properties.

On the General tab, examine the number that is listed under Registered to:

System administrators may find it useful to check the product ID through the Registry Editor.

The registry path is:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\ CurrentVersion\ProductId

Licensed customers are not affected by this anti-piracy change.

update instalation will fail on computers with the following product IDs:


XXXXX-640-2001765-23XXX 21:50 25 Sep 05

I did a complete reinstall and everything works perfectly

Thanks to everyone for your help.

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