Docker toolbox with Visual studio - Volume sharing is not enabled

I'm trying to get running a docker support with Visual studio 2017 for a .net core 2.0 web app running on linux containers. I'm working on machine with win 7 OS, so I must use a Docker toolbox with Virtual box. I've already checked this question: How to get docker toolbox to work with .net core 2.0 project, but I got stuck in the following problem, when trying to run it with VS:

Volume sharing is not enabled. Enable volume sharing in the docker ce for windows settings

So far I know that there is a default volume mounted under the C:\Users, so my project files should be copied somewhere under this folder in case I don't want to mount any other volume. So I copied them there.

When I check the settings of my Virtual box, folder seems to be shared:

I can even cd into this folder with command line, but still can't get over this problem. Any ideas about this?

Finally I got this running. Error message comming from VS is very misleading and it has nothing to do with volume sharing. Eventually I realized that problem is in running a debugger, because when I ran solution with Ctrl + F5 everything was ok and container started correctly. Problem occurred only when running with F5 and trying to attach a debugger.

Then I found some clues in console output. VS tries to download some tooling for debugging containers with powershell script named GetVsDbg.ps1. When running this script I could observe errors like:

Add-Type : Cannot add type. The assembly 'System.IO.Compression.FileSystem' could not be found.

Finally I fixed this issue by updating powershell version which was somehow in collision with my .net framework installed on my machine.