Fix-AppxPathExpandSZ.ps1

$k = 'HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Appx\AppxAllUserStore\Applications'
Get-ChildItem -Path $k -Recurse | 
Where-Object { $_.PSIsContainer} | 
ForEach-Object {
    $p = $null
    if ($p=Get-ItemProperty -Path "$($_.PsPath)" -Name 'Path' -ErrorAction SilentlyContinue) {
        $App =  Split-Path $_.Name -Leaf
        Write-Verbose -Message "Dealing with $($App)" -Verbose
        if ($p.'Path' -match '%SYSTEMDRIVE%\\') {
            Write-Verbose "$($App) has a wrong path set in the registry" -Verbose
            $v = $p.Path
            try {
                Set-ItemProperty -Path "$($_.PsPath)" -Name 'Path' -ErrorAction Stop -Value $v -Type ExpandString
            } catch {
                Write-Warning -Message "Failed to fix $($App) because  $($_.Exception.Message)"
            }
        }
    }
}