UpgradeTools/Install-ExtensionsFromFolder.ps1

$ExtensionsDir = dir "C:\Disks\Microsoft\Business Central\Dynamics365BusinessCentral GB\Extensions" 
$ServerInstance = 'EI_NAV130_WIN_LIVE'

foreach ($Dir in $ExtensionsDir){
    Get-ChildItem -path $Dir.FullName -Filter *.app | 
    Foreach-Object {
            Publish-NAVApp -ServerInstance $ServerInstance -Path $_.FullName
    }
}