Visual Studio 2015 - Razor IntelliSense not working
When editing *.cshtml files in Visual Studio 2015 I do not get any IntelliSense for Razor operators. e.g. If I type @Html. I don't get any hints come up.
In addition, rather suspiciously, when I open a *.cshtml file for the first time I receive the error
An exception has been encountered. This may be caused by an extension. You can get more information by examining the file 'C:\Users\[username]\AppData\Roaming\Microsoft\VisualStudio\14.0\ActivityLog.xml'
That ActivityLog file can get pretty big, so if you're going to examine it, it's probably best to delete it first and regenerate the error. In mine there was a fairly obvious error jumping out at me:
System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.ArgumentException: Item has already been added. Key in dictionary: 'RazorSupportedRuntimeVersion' Key being added: 'RazorSupportedRuntimeVersion'
And so on.
The proposed solution for this around the web is to run devenv /resetuserdata. This failed immediately for me as for some reason that command tried to launch Visual Studio 2010, which isn't installed. Fortunately, there is a fix for this too. That's a regedit tweak to: HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths\devenv.exe. The default value is the path to the current Visual Studio installation, so for me I just needed to replace "10.0" to "14.0" in the file path and the command worked.
Mine still popped up with "Unknown Error" during the reset process, but once I launched Visual Studio (and gone through initial setup again) it all worked as expected.