If SP3 installed succesfully, all is fine. No need for older servicepacks.
Kees
On my old computer I had XP but I decided to try Ubuntu for a while.(P4,2GB memory).After dissatisfaction with the Ubuntu . Now to replace XP I bought a disc without key number, since I had my number on the case. (I had misplaced my original XP disc)
This disc I bought , had XP Home and Pack 3,which I loaded and every thing went well. Now I find difficult to load Service Packs 1&2. I am not sure if the issue has anything to do with the disc I bought, I have updates loaded other than the packs.
Are these Packs necessary to the working of the computer. The computer seems to work OK.I have installed free anti-virus protection.
I have found my original disc as well. I wish to continue with XP as long as I can.
Should I reload the original XP?
Or leave it be and find a way to load the missing packs.

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