This is a known bug that we have fixed in VS 2015, however you could have been affected if you installed the “Universal Windows App Development Tools” during a specific period of time. We will soon be publishing a KB with the following workaround:
If the “Universal Windows App Development Tools” are still installed:
- Go to Programs and Features, select Visual Studio 2105, click Change.
- In Visual Studio setup, click Modify.
- Deselect the feature “Universal Windows App Development Tools”
- Select “Universal Windows App Development Tools” again, and click Update.
If you have already uninstalled the “Universal Windows App Development Tools”:
- Reinstall “Universal Windows App Development Tools”
- Or, take the following steps to reinstall the JavaScript project system and language service:
- Download the installer for your edition of Visual Studio, e.g.
vs_community.exe
. - Open a CMD window, and run the following command:
vs_community.exe /modify /installselectableitems JavaScript_Hidden /passive
- Download the installer for your edition of Visual Studio, e.g.
Sorry for the trouble. Hope that helps.