I have Windows 7 Professional, but it was an upgrade. I'm really wanting to wipe my drives and do a clean install, but don't know if I can do a clean install of Windows 7 with my key since it was originally an upgrade. Will that matter at all?
If you wipe the HD (a good idea) then when the Upgrade version DVD boots it will scan the HD for any OS, see none and reject Upgrade version key upfront.
In that case, leave the key blank and wait until after install to do one of the workarounds in the tutorial posted Ageeb posted above. I find the registry change to be easiest. Then activate with key at Computer>Properties.
As long as you have a qualifying XP or Vista on hand and don't use it again while using Upgrade version, you have met the terms of the EULA. Neither need to be installed.
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