Hey, I have worked on 2 dells in the last 3 weeks, both needed a reinstall of OS because of viruses and such, when i ran everest on both of them before i reinstalled they both said the computers had different serials than what was on the COA on the side of the case, also, when i reinstalled it did not ask for the serial and both came back with the serial it said before i reinstalled, also, the serials used were not the same, but im not sure on that because one was XP pro and the other was home...wats up with this...