Fixing "Extension could not be found" error

Occasionally when working on Code Connect and Alive Visual Studio would cease to build our VSIX package. The error we would see said Extension '<GUID>' could not be found. Please make sure the extension has been installed.

screenshot of the error

We found a few solutions online but none of them worked for us. Eventually we worked out a very simple solution:

Solving Extension could not be found

To get Visual Studio to build the solution, open the extension’s main project’s properties. Navigate into Debug tab. Under Start Options, clear Command line arguments

video screenshot of the solution

Hit Ctrl+Shift+B to build the solution. Once it builds, restore Command line arguments to /rootsuffix Exp (or anything that was there previously) and build again.

This time the package will be built and the extension will be deployed to the Experimental Instance of Visual Studio.

Update: Another solution

This section was added on 2016.01.14

The above fix doesn’t always work. Zpqrtbnk pointed out that the error can be corrected by manually launching and closing the experimental instance of Visual Studio.

start experimental instance

It looks like closing the experimental instance fixes its state. After power-cycling VS like this, you should be able to build and deploy your package.

Other solutions

Other solutions that we’ve found, but didn’t always work for us

Good luck!

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