I installed a new copy of Windows XP but got an error saying "invalid product code" and Microsoft refuses to activate. Is there anything I can I do or must I take it back to the store?
That really depends on the specific issue with your product code. The store that sold you the PC should have provided you with a paper license that contains a watermark and hologram with your license code. (see
for more details.)
Some unscrupulous shops don't want to pay Microsoft's license fee and load a version of XP using a pirated license code, or a code that has been used before. If you do not have the paper license, go back to the store and demand one. If you do have the paper license, make sure that you are typing in the information correctly (the numbers 8 and 5 often looks like a B and S). If the store won't help you, report the problem to Microsoft's piracy center http://www.microsoft.com/resources/howtotell/ww/default.mspx
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