Installing PowerShell module persistently for all users

PowerShell can only "see" modules installed in one of the directories listed in $env:PSModulePath. Otherwise you'll have to import the module with its full path.

To make a new module visible to all users you basically have two options:

1. Install the module to the default system-wide module directory (C:\Windows\system32\WindowsPowerShell\v1.0\Modules).
2. Modify the system environment so that PSModulePath variable already contains your custom module directory (e.g. via a group policy preference).

The latter will only become effective for PowerShell sessions started after the modification was made, though.

This profile applies to all users and all shells.

%windir%\system32\WindowsPowerShell\v1.0\profile.ps1

After taking the steps you spelled out in your question (which I think is the general way to go), I found two ways to get the new module source recognized by Powershell:

• Restart the machine. (Works every time.)

• Reset the PSModulePath in each open session.

  $env:PSModulePath=[Environment]::GetEnvironmentVariable("PSModulePath", "Machine")

  I found this was necessary to run in both normal and elevated prompts to get this to work without restarting in each type of prompt. (See also the conversation @ Topic: PSModulePath.)