Re-Arming Vista's Trial After Expiration

Windows Vista can be installed without a product key in a 30-day trial mode. This is nice for users who may want to try out Vista, or compare the different flavors (Home Basic, Home Premium, Business, Ultimate, etc). After 30 days, you are required to activate Vista by entering a valid product key, which will then lock it in to a particular edition depending on the key (Vista also supports instant upgrades, so you can change editions later).

As Jeff Atwood points out, you can extend the grace period to 120 days using the re-arm command. It's easy, it's legal, and it's provided by Microsoft. And ideally, you'll extend the grace period BEFORE the 30-day trial is up.

My Vista 30-day trial ran out on my media center PC, and I was given only four options the next time I tried to login: activate now, re-enter my license key, use reduced functionality mode, or logout. I'm not ready to activate, and I don't have a license key. I don't want to logout -- I want to watch TV! This leaves "reduced functionality mode," which is only an IE browser window (you're supposed to use it to buy Vista online). I remembered the re-arm command, but reduced functionality mode doesn't provide a Command Prompt, the Start Menu, Desktop, or anything else -- just a single IE window.

Fortunately, there's an easy workaround (or maybe several. Safe Mode seems like a reasonable option, but I didn't want to reboot). IE's address bar can be used to browse the file system to open web pages stored locally. It can also be used to launch c:\windows\explorer.exe, which starts up the rest of the Windows environment and gets you out of reduced-functionality mode. From there, I opened a command prompt with elevated privileges and ran "slmgr -rearm" to extend the trial period by another 30 days.