I have this issue before when using Windows Vista.
I formatted and reinstalled Windows Vista. for what, 10+ times?
When I was using Windows Vista and tried to activate online, it refused to activate and wanted me either purchase a new Windows Vista Home Basic key or using telephone to activate or seek help from Microsoft.
Of course, I used the Telephone activation procedure and I talked to the operators and they cooperately and politely have provided me the activation ID, thus activation successful.
A month ago, I get a clean, retail, genuine version of Windows 7 Ultimate key via some forum website (they are attempting giveaway Windows 7 keys). I formatted and installed Windows 7 Ultimate and used the key to activate -- successful. Activated online,
checked via Microsoft Genuine Advantage Diagnostic Tool and Windows Genuine website -- all pass.
I was wondering, if I were to reformat my system and reinstall Windows 7, how many times does Windows accept by activating using the same key without purchasing a new one/activate via telephone?