You can extend the 30 days evaluation period of Microsoft Windows 7 for 3 times. That means, if you do not enter a product key during the setup of Microsoft Windows 7, it will automatically run in evaluation mode for 30 days. After this period, you can extend the evaluation period for another 30 days. This procedure can be repeated three times. Rumours say, that even this behavior can be changed..
When you setup Microsoft Windows 7, the setup asks you for a product key.
If you don’t enter a key, setup will put Microsoft Windows 7 automatically in evaluation mode. This works for 30 days. After this period, you can extend the evaluation period for another 30 days using slmgr.vbs
Consider, this command must be run as administrator!
This procedure can be repeated 3 times. I don’t know if it is true, but rumors say, that even after repeating this step 3 times, a registry key can be changed and the procedure using slmgr.vbs can be applied again and again ..
"SkipRearm"=dword:00000001 <---set it to: dword:00000000
feel free to comment, post your experiences!