Do I need Service Pack 1 installed before applying Service Pack 2?
No, Service Pack 2 includes most updates released and tested on the date it was released. Updates released after Service Pack 2 will need to be applied after running the Service Pack 2 update. You should access Windows Update immediately after applying Service Pack 2 to get critical updates issued after Service Pack 2's release.
Try installing Windows XP Service Pack 2 this way:
1. Do not use Express Installation.
You can order the Service Pack 2 CD.
Or:
Download the Network Installation from here: (be sure to select the correct language)
Download Windows XP Service Pack
DSL takes about 20 minutes, if you do not have high speed access, get a friend to D/L SP2 for you.
Then burn it to a CD and keep for the future and sharing with friends.
read the rest from the below.
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Service Pack Installation Checklist
http://www3.telus.net/dandemar/spackins.htm
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