Download Powershell 5.1 For Windows Server 2012 R2 -

Name Value ---- ----- PSVersion 5.1.14409.1012 PSEdition Desktop PSCompatibleVersions 1.0, 2.0, 3.0, 4.0... BuildVersion 10.0.14409.1012 CLRVersion 4.0.30319.42000 WSManStackVersion 3.0 PSRemotingProtocolVersion 2.3 SerializationVersion 1.1.0.1 If PSVersion shows 5.1.x, success. | Issue | Solution | |-------|----------| | Installation fails with “The update is not applicable to your computer” | Ensure OS is Server 2012 R2 (not RTM 2012). Install all important Windows Updates first, especially servicing stack updates. | | Missing .NET Framework error | Install .NET 4.8 from https://dotnet.microsoft.com/en-us/download/dotnet-framework/net48 | | WMF 5.1 not appearing after reboot | Check Get-HotFix -Id KB3191564 . If not present, reinstall. | | PowerShellGet missing | Run Install-Module PowerShellGet -Force after v5.1 is installed. | | Antivirus blocks MSU extraction | Disable AV temporarily or extract MSU using expand -F:* *.msu destination_folder | | Error 0x800f081e – CBS_E_NOT_APPLICABLE | Server missing required updates. Run DISM /Online /Cleanup-Image /RestoreHealth then Windows Update. | Step 7: Optional – Install NuGet and PowerShellGet Even with PS 5.1, some environments need a newer PowerShellGet module:

Also check .NET version:

wusa.exe "C:\path\to\Win8.1AndW2K12R2-KB3191564-x64.msu" /quiet /restart After reboot, open PowerShell as Administrator and run:

$PSVersionTable Expected output snippet:

| Requirement | Details | |-------------|---------| | | Windows Server 2012 R2 (x64). Not for Server 2012 (non-R2). | | Administrative access | Local Administrator rights required. | | Internet connection | To download the update package. | | Sufficient disk space | ~500 MB free. | | Windows Management Framework (WMF) 5.1 | This is the official installation package for PowerShell 5.1. | | .NET Framework prerequisite | .NET Framework 4.5.2 or higher is required. Ideally install 4.8. | ⚠ Important: Do not install WMF 5.1 on Server 2012 R2 if it runs critical applications like Exchange Server, SharePoint, or System Center unless explicitly supported by their vendors. Microsoft supports WMF 5.1 on Server 2012 R2 but application-level compatibility must be verified. Step 1: Check Current PowerShell Version Open PowerShell as Administrator and run:

Write-Host "Installing PowerShell 5.1..." -ForegroundColor Cyan Start-Process wusa.exe -ArgumentList "$msu /quiet /norestart" -Wait