Dell 9100 Windows 7 Build 7601 This copy of Windows is not genuine

This does happen, sometimes when you change hardware or re-install the OS. You will need to get to a  page wher it describes what you do to re-register. There will be a long series of numbers/letters. However, I seem to have a bout of "old-timers" memory and can't remember exactly how you get this; perhaps a web search. Then you call a MS automated line which will ask for the code and then give you another long code that you input to the computer, and it's done. Sorry that I can't remember the whole procedure.

Dell Tech support deleted a windows update KB 971033 from 2010

then updated windows

This does happen, sometimes when you change hardware or re-install the OS. You will need to get to a  page wher it describes what you do to re-register. There will be a long series of numbers/letters. However, I seem to have a bout of "old-timers" memory and can't remember exactly how you get this; perhaps a web search. Then you call a MS automated line which will ask for the code and then give you another long code that you input to the computer, and it's done. Sorry that I can't remember the whole procedure.

Press [Windows] and [ r ] type in slui in the run box and see if you can activate Windows. If you can't activate Windows type in slui 4 (with the space), this will ask you your country and bring up the phone activation wizard. See Windows Reinstallation Guide/A Clean Install of Windows 7 Step 11 Microsoft Product Activation(page 40):

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