Hi emacoman,

Welcome to the community.

To reinstall factory installed windows you would not require to enter the product key. So you can reinstall the windows anytime without using the product key.

Please make sure that you are reinstalling windows from disk supplied by us. If you have any further queries please feel free to contact us.

Thanks and Regards
Sandeep P
#iworkfordell

See Windows Reinstallation Guide for more details:

http://philipyip.wordpress.com/dell-community-forums/ 

Hallo, Dell Support...

So I have the same problem that the other guy. The product key and the serial ( the information on the button of the laptop) are unreadable. And is asking me for the key product. I called yesterday to dell support and told me that it's necessary to buy a license ...however my product has one licence for two systems (XP and Vista) ...so I have the question if i made something wrong when i reinstalled..

Thanks and advanced for your kind and prompt reply.

Did you install Windows Vista Business Edition or Windows XP Professional using downgrade rights from Windows Vista Business?

If so did you use a Dell Windows Vista Business Reinstallation DVD or a Dell Windows XP Professional Reinstallation CD?

Did you initiate the Windows install via the Windows Desktop or via the Dell BIOS screen?

Hello!!!

Well I put the Windows XP CD, because I didn't want to change of the Operative Systems (that's why i didn't use the BIOS screen), I needed to reinstalled because , stupidly, I install a virus u.u

Thanks for answer me. 

Regards,