I don't know if it's a common issue or not, only that I've never encountered it. The next time you're booted into Windows, try to install it and tell me what happens and at what point in the installation process the error pops up. To tell whether your computer has SP1 the easiest way IMHO is to hold down the command key and hit "R" on the keyboard to open a run prompt. Type in "winver" and hit enter to see what version of Windows your computer is running.