Can't install nuget package because of "Failed to initialize the PowerShell host"

Question

All of a sudden, I am getting this error when upgrading Nuget packages. None of the fixes that I have come across work. I am using Visual Studio 2013.

'Newtonsoft.Json 6.0.3' already installed.

Adding 'Newtonsoft.Json 6.0.3' to Tournaments.Notifications.

Successfully added 'Newtonsoft.Json 6.0.3' to Tournaments.Notifications.

Executing script file 'F:\My Webs\BasketballTournaments\MainBranch\packages\Newtonsoft.Json.6.0.3\tools\install.ps1'.

Failed to initialize the PowerShell host. If your PowerShell execution policy setting is set to AllSigned, open the Package Manager Console to initialize the host first.

Package Manager Console

Attempting to perform the InitializeDefaultDrives operation on the 'FileSystem' provider failed.

If I wait for the initialization to finish in the console I was able to add some packages.

Answer 1

Setting an execution policy to RemoteSigned or Unrestricted should work. It must be changed under an administrator mode via a PowerShell console. Be aware that changes will be applied according to the bit version of the PowerShell console, so 32bit or 64 bit. So if you want to install a package in Visual Studio (32 bit version) which requires a specific policy you should change settings of the policy via PowerShell (x86).

The command in PowerShell (as administrator) to set the policy to unrestricted (as noted by @Gabriel in the comments) is:

start-job { Set-ExecutionPolicy Unrestricted } -RunAs32 | wait-job | Receive-Job

Having set the policy to unrestricted, you will want to set the policy back to its original after the install is complete.