Never heard of this one either. FCKGW on the other hand still triggers muscle memory.

I had FCKGW-RHQQ2-YXRKT-8TG6W-2B7Q8 memorized too but I used XGCJ6 more often. Mostly for Virtual PCs that I was converting to hyper-v guests.

> Might need some background on this one.

It's a VLK. During early XP days, Volume License Keys were widely accepted and when using them, XP would show as activated.