How to: Upgrade from a Trial Edition of Visual Studio
You can evaluate the Professional, Premium, Ultimate, and Test Professional editions of Visual Studio 2012 for up to 90 days, starting when you install the product. You can use the trial edition of Visual Studio Test Professional for 90 days without registering it, but you must register the trial editions of Visual Studio Professional, Visual Studio Premium, and Visual Studio Ultimate within 30 days after you install them to use them for a total of 90 days. If you don't register the trial editions of Visual Studio Professional, Visual Studio Premium, and Visual Studio Ultimate within 30 days, the trial period expires 30 days after you install them.
For example, if you download and use Visual Studio Premium for 10 days and then register it, you can use it for an additional 80 days. To continue to use the product after 90 days, you must provide a valid product key. For information about how to locate the product key, see How to: Locate the Visual Studio Product Key.
The trial period for any Express edition of Visual Studio 2012 doesn't expire if you register the product within 30 days after you install it.
Before you upgrade, we recommend that you download and review the Visual Studio 2012 and MSDN Licensing White Paper from the Microsoft website.
For additional assistance, go to the Microsoft Support website, and then navigate to the Visual Studio Solution Center.
To upgrade from a trial edition of Visual Studio Professional, Premium, or Ultimate
Start Visual Studio in Run as Administrator mode.
On the menu bar, choose Help, Register Product.
Specify the product key, and then choose the Next button.
To upgrade from a trial edition of Test Professional
Start Microsoft Test Manager.
Choose Home and then, on the menu on the right side, choose About.
In the Product key section, specify the product key, and then choose Activate.
If trial editions of Visual Studio Ultimate and Visual Studio Test Professional are installed on the same computer, you must provide a product key in only one of them to activate both of them.