I live in terror of the number of less then authentic XP installs that will surface with an attempt to install Service Pack 2. And in equal terror of perfectly legitimate licenses with the same problem.
. if you used any tricks to circumvent the authentication process for Service Pack 1, forget about it. You (until the hacker community gets up to snuff), will not be able to install Service Pack 2. The bar has been raised, and Microsoft offers no apologies.
. There will be a ton of installations where the original was BIOS-lock activated (you buy a Dell, for example, and XP is installed and does not require activation) and you will be asked to authorization in order to download and install Service Pack 2. Answer: Call Microsoft. Read the COLA number on the underside, left, right or rear of the case. There will not be an issue with authenticating your computer.
. You have a legit copy of XP, all updates, and Service Pack 2 install objects as to your license. Do not get mad: just call Microsoft. They will authenticate you, and explain how to obtain and install Service Pack 2.
In a later and new thread I will give you my best thoughts as to how to deploy this service pack on a workstation. (Hint: slipstream, and do a repair upgrade/reinstall, but this might change).