I've just encountered the following error while trying to integrate SP2 into a XP Professional including Service Pack 1a using the XP Update tool

"This Service Pack cannot be integrated into a destination that also has integrated software updates"

Any Ideas???

I used this command to integrate SP2 to WinXP-Pro-SP1a with no problems:

I:\XPsp2.exe /integrate:C:\XPCD, where I:\ is my CD-ROM drive.

There appears to be issues slipstreaming sp2 over sp1,(don't know about sp1a)? I know it hasn't worked for me & has been successful from the gold version only.

That happens because you have hotfixes slipstreamed through svcpack. Try to remove it and try again

It seems that Dell OEM CDs have hot-fixes integrated.

You need to delete a folder called "SVC*" and also "svcpack.inf" in I386. After that the slip-stream will happen fine.

All the best, do tell us how it goes.

And once youve deleted those files you may come up with an error message when trying to install - check this link IF you do

http://www.msfn.org/board/index.php?showtopic=28193