Error message 'Value cannot be null. Parameter name: userContext' in Visual Studio 2017

Question

I get error message

'Value cannot be null. Parameter name: userContext'

in Visual Studio 2017 when trying to click notification or opening Extensions and updates from tools folder. Before answering can you look this Answer. The answer did not work on me.

Answer 1

I had same problem to. My solution is quite similar from Tahir Hassan.

1. Go to ...AppData\Local\Microsoft\VisualStudio\15.0...\ delete the file "privateregistry.user.bin"

2. Start Visual Studio -> VS only ask to sign in or not.

You don't have to download any updates after that.

Answer 2

I had this problem. Close VS, go to %LOCALAPPDATA%\Microsoft\VisualStudio\ and delete/rename a folder whose name starts with 15.0_.

Then start Visual Studio, then download and install the latest update.

After that it should work - Best of luck.