guard to exit script if agent is installed

Install-ESETManagementAgent.ps1

@@ -1,5 +1,11 @@
 # NOTE: The $CONFIG variable must be set by the calling script
 
+# Exit this script if agent is already installed
+If ( Test-Path "${Env:ProgramFiles}\ESET\RemoteAdministrator\Agent\ERAAgent.exe" ) {
+    Microsoft.Powershell.Utility\Write-Output "ESET agent is already installed. This script will now exit."
+    Return
+}
+
 # Set path to temp directory
 $TEMPDIR = '{0}eset-protect-deployment' -f (Get-TempPath)
 

Install-EmberkomCloudBackup.ps1

@@ -15,17 +15,18 @@ switch ( $Edition.ToLower() ) {
 # Install and import additional Powershell module
 Import-MSP360Module
 
-# Install the agent if it's not currently installed
-If ( -not $(Get-MBSAgent) ) {
+# Exit this script if the agent is already installed
+If ( $(Get-MBSAgent) ) {
+    Microsoft.Powershell.Utility\Write-Output "Backup agent is already installed. This script will now exit."
+    Return
+}
 
 # Download the installer
 $Installer = Download-File -URL $URL
-
 # Install the agent
 Write-Output "Installing Emberkom Cloud Backup agent"
 Try { Start-Process "${Installer}" -ArgumentList "/S" -Wait }
 Catch { Write-Error $_.Exception.Message }
-
 # Add backup user to installed product
 Try {
     $MSP360Password = ConvertTo-SecureString -string $MSP360Password -AsPlainText -Force
@@ -33,16 +34,13 @@ If ( -not $(Get-MBSAgent) ) {
     Add-MBSUserAccount -User $MSP360Username -Password $MSP360Password
 }
 Catch { Write-Error $_.Exception.Message }
-
 # Wait a few seconds to let the agent check-in
 Start-Sleep -Seconds 10
-
 # Set the agent edition
 # Note: the product edition must be set *after* the user is added
 Write-Output "Setting Emberkom Cloud Backup agent edition to ""$AgentEdition"""
 Try { Set-MBSAgentSetting -Edition $AgentEdition -Verbose }
 Catch { Write-Error $_.Exception.Message }
-}
 
 # Delete the desktop icon
 If ( Test-Path "${Env:PUBLIC}\Desktop\Emberkom Backup.LNK" ) { Remove-Item -Path "${Env:PUBLIC}\Desktop\Emberkom Backup.LNK" -Force -ErrorAction SilentlyContinue }