How do I put Service Pack 2 on my old Windows XP CD?
Stuart Jordan, via e-mail
You need to combine SP2 with your XP system CD to create a new hybrid disc with everything on it--a procedure called "slipstreaming."
Why bother? Well, if your Windows CD is a significantly earlier version than your current installation, you're asking for trouble: Your repair and reinstall options are limited, and you can't create a bootable CD from an original XP CD (go to "Create a Windows CD for PCs That Don't Have One" for information on creating a boot CD using the free BartPE utility).
If your PC came with XP but without a system CD, you might be able to use the i386 folder on your hard drive as a virtual system CD. If your hard drive has more than one i386 folder, look in your C: drive's root folder or inside the C:\Windows folder. It will contain the files expand.exe, regedit.exe, and winnt32.exe.
You'll also need the single-file version of the Windows XP Service Pack 2 update, which you can download immediately.
And you'll need a program to do the streaming. I recommend AutoStreamer; it's free, easy to use, and fast. AutoStreamer's wizard asks whether you want to use a Windows CD or a "share" (your i386 folder). Point it to your Service Pack 2 file, and it will create an image of your new CD with both your original Windows CD and SP2 as an .iso file. Burn a CD from that .iso file with Nero Burning, Easy Media Creator, or another disc-authoring program, such as the free ISO Recorder.