Four months of Windows 7 free? It sounds unlikely, but those are the claims being made. Reports on the Windows Secrets say that the initial 30-day free trial can be extended three more times, much as what happened with Vista.
If you install Windows 7 after it’s shipped on October 22, but don’t enter the installation key, the 30-day clock begins running. As your time almost runs out, Windows Secrets says, you can “click Start, All Programs, Accessories. Right-click Command Prompt and choose Run As Administrator. Enter your administrator password.” After that type the command “slmgr –rearm” and restart the OS. Bingo, you have another 30 days.
“You can run the -rearm trick a total of three times,” the site claims. “If you perform a -rearm at the end of each 30-day period, you end up with 120 days of full, unfettered Windows 7 use without having to supply an activation key in the interim.”
However, the trick evidently only works with that command on Windows 7 Home Premium, so be warned.