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words what come from the mind of @hadricus (nathan manzi).

Installing a .nupkg on an offline machine

Posted on 22 January, 2020 / 1 min read

The ability to find and install PowerShell modules from online sources like Nuget makes life for a Windows admin a smidge nicer. On the flipside, arbitrary trust of online package repositories and granting servers outbound internet access can be a nightmare for those tasked with protecting a network.

You might find yourself needing to install a PowerShell module (as a nupkg file) on a system with restricted (or no) internet access, as one of our security consultants found himself needing to do.

Here’s a quick guide on how to achieve this. If only it were as simple as Install-Package .\module.nupkg!

  1. Run Install-PackageProvider -Name NuGet -RequiredVersion 2.8.5.201 -Force to install the provider from a computer with an internet connection.
  2. After the install, you can find the provider installed in C:\Program Files\PackageManagement\ProviderAssemblies – copy the Nuget folder to external media or otherwise find a way to get it to your target system.
  3. Place the nuget folder in C:\Program Files\PackageManagement\ProviderAssemblies on your target computer.
  4. Start a new PowerShell session on the target computer to auto-load the package provider.
  5. Create a new folder in C:\ named Packages
  6. Copy your nupkg file(s) into C:\Packages
  7. In PowerShell run Register-PSRepository -Name Local -SourceLocation C:\Packages -InstallationPolicy Trusted
  8. You can list the packages available with Find-Module -Repository Local
  9. Run Install-Module -Name <YourModuleName> where <YourModuleName> is the name of your package as returned by the command in step 8.

I put this together with information from trebleCode and Nova Sys Eng in this StackOverflow thread. Thanks go out to those fine people.



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