Problem occurred extracting the vsix to the experimental instance.

I am using VS2017 and I have a new extensibility project based on the latest extensibility templates.

When I build my project, a problem is occuring when the VSIX is being extracted to the experimental instance install location:

```

ErrorProblem occurred while extracting the vsix to the experimental extensions path.

DnnProjectSystem.ProjectTypeC:\Users\Darrell\Source\Repos\DnnProjectSystem\src\packages\Microsoft.VSSDK.BuildTools.15.0.26201\tools\vssdk\Microsoft.VsSDK.targets680

```

There appears to be a problem occuring in the Microsoft.VsSDK.targets file, when extracting the VSIX to the experimental instance's install directory. However I can't fathom what this problem might be.

I have looked at the VSIX in the output directory, and I can unzip the VSIX manually without any errors.