Running Test Driven .NET / Gallio MBUnit / .Addin Plugins In VS2011 Developer Preview

Background (Safe to skip)

I have been using Visual Studio 11 as primary IDE instead of Visual Studio 2010 at work all day. Details of that might come in a later post, for now, this is on a specific problem. Getting TestDriven.NET to work with Visual Studio 11.

The current project uses MbUnit for number of Selenium functional tests locally and on CI servers. We used to run those using Resharper 5.x in Visual Studio 2010. When Resharper 6 came out, the Gallio / MbUnit Resharper plug-in that made running those tests possible was not compatible with it (and still is not to the date of this post), so, we used TestDriven.NET instead.

When Visual Studio 11 Developer Preview came out,, all installed plug-ins didn’t work with it.

Plugins are two types:

  1. Visual Studio Extensions: Downloaded from Visual Studio Gallery usually,, which is browsable from the IDE Tools-> Extensions Manager menu
  2. Old Style Addins: Usually have their custom installers, which basically drop a ".addin" file (which describes the add-in to Visual Studio) along with the DLLs that make the plug-in. The default location is My DocumentsVisual Studio 2010<or 11 for the preview>Addins. Sometimes, addins are in other locations as well.

TestDriven.NET comes under the 2nd category.

Test Driven .NET With Visual Studio 11

To get the TestDriven.NET plug-in working with Visual Studio 11, we need we first need to get the location of the TestDriven.NET installation. For me the path was C:Program Files (x86)TestDriven.NET 3.

Go to this folder, you should find a file named "TestDriven2010.AddIn". Make a copy of this file, and rename the copy to "TestDriven11.AddIn".


Run Notepad as administrator (Right click it and choose "Run as administrator"),


Click File->Open, and browse to  the "TestDriven11.AddIn" file (You’ll need to choose "All files" from the file type drop down).


The file should look like that:


Change <Version>10.0</Version> to <Version>11.0</Version>.


Save the file, and close this.


Next step, we need to get Visual Studio 11 to recognize this file. The easiest way is to add the TestDriven.NET folder to the paths that Visual Studio looks searches for addins.

To do this, open Visual Studio 11, Go to Tools->Options, then from the left tree view, browse to Environment->Add-in Security


Click, Add, and enter the folder of TestDriven.NET installation on your machine, where the .addIn files were found, and press OK


You should be able to see the folder down the list, and press OK to save the change.


You may get a messaging saying you need to restart Visual Studio for the changes to take place.

Restart Visual Studio, then go to Tools->Add-in Manager. You’ll find TestDriven.NET in there, make sure it’s enabled (or enable it by ticking the check-boxes) as below:


Now, your Test Driven.NET addin should work nicely.




Remember, you can apply the same to any .AddIn Visual Studio plug-in.


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