How to Extend the Windows 7 Activation Trial Period from 30 to 120 Days

There’s an easy way to stretch Windows 7′s 30-day free-trial period to 120 days so you can determine whether Microsoft’s new operating system meets your needs. It is not a hack, it is a system put in place by Microsoft to give you more time to evaluate it.Microsoft allows anyone to install and use any version of Windows 7 for 30 days without having to enter an activation key. There are no strings attached, and the operating system’s performance is not degraded or defaced during the trial.

Fortunately for us, the 30-day grace period can be extended up to three additional times — to a total of 120 days — using a Microsoft-supplied utility called the Software License Manager (slmgr). This tool conveniently ships with Windows 7.