Extending the Windows Vista Trial Period

I’ve been building a VPC (Virtual PC Hard Drive) for the Microsoft Developer Evangelists in the field. It’s a Windows Vista Ultimate installation with a reasonably complex collection of PHP demos.

When you install Widows Vista you have 30 days before you have to Activate Windows.

I built the VPC more than 30 days ago !!!

Today I finally got around to finalize the details and my 30 day trial has expired. BUMMER !

When I started up Windows Vista, I get the message “This installation of Windows is not Authentic” (or something close to that).

Now – if I wanted to extend the 30 day trial for another 30 days (Up to 120 days total) and I thought to do it BEFORE the first 30 days expired, it’s not a difficult thing to do. But, once you are PAST the 30 days, you don’t get the Windows interface (not Start Menu so no command prompt.)

When you click on the link that lets you ruin Windows Vista in “Limited Functionality” all you get is a browser that takes you to a web site where you can buy Windows Vista. There is NO desktop and if you close the browser Windows Vista shuts down.

Now, I don’t want to Activate Windows Vista because this VPC is going out to hundreds of folks inside Microsoft. (And I wanna KEEP my job!)

But, I also don’t want to have to start over and recreate my VPC from scratch.

So, here is how I managed to do to extend the trial period and save myself a few days of necessary work.

In the Internet Explorer window that opens to take you to a site where you can purchase Windows Vista….

Do this:


When you hit return you will get here:


Then, navigate to the C:\Windows\System32 directory and find the cmd.exe file in Explorer.


Right Click on cmd.exe and select “Run as Administrator”.

In the command shell type: "slmgr -rearm" and hit enter.

Now – REBOOT Windows Vista Inside your VPC.

VIOLA ! – You have another 30 days to try out Windows Vista.

Note: extending the evaluation period is not a violation of Vista's end user agreement.

Comments (3)

  1. The Virtual PC / Virtual Server or VM Ware are excellent virtual environments for students to learn the

  2. The Virtual PC / Virtual Server or VM Ware are excellent virtual environments for students to learn the

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