Dear Lifehacker, I have a question regarding Windows 7 Home Premium. I bought it and installed it on my laptop about four years ago. A few weeks ago I experienced some technical problems with my browser and had to reboot my laptop and reinstall the OS. However, I can't use the Internet anymore because my new installation hasn't been authorised. Unfortunately I don't have my product key any more. What can I do? Can I purchase a new discounted product key or am I stuck with buying a whole new copy? Thanks, Locked Out
The issue you've got isn't an uncommon one, and unfortunately it's not one that's likely to end cheaply for you.
The first step I'd advise would be to call Microsoft and explain the situation.
Any supporting documentation you have that could verify your previous installation (like, for example records of previous calls to Microsoft or emails verifying details) may help in convincing them of your bona fides, and they may be sympathetic and provide you with an authorisation key.
Failing that, however, you're probably stuck with buying a new copy. The lesson for everyone else? Remember to use tools like Magical Jelly Bean Key Finder to verify your keys before any future fresh installs.
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