Re-implemented force cleanup via AgentCleanup4

Author: AngryProgrammerInside

Agent/AgentCleanup4.exe

@@ -612,6 +612,7 @@ $Script = @{
     "Library"     = @($SC.Paths.TempFolder, "Lib") -join '\'
     "PartnerFile" = @($SC.Paths.TempFolder, $SC.Names.PartnerConfig) -join '\'
     "TempFolder"  = $SC.Paths.TempFolder
+    "AgentCleanup" = @($SC.Paths.TempFolder, "AgentCleanup4.exe") -join '\'
   }
   "Results"    = @{
     "EventLog"           = $SC.ScriptEventLog

Agent/InstallAgent.ps1

@@ -679,6 +679,7 @@ function ValidatePartnerConfig {
     $Config.NETVersion = $InstallInfo.NETVersion
     $Config.NETFileVersion = $InstallInfo.NETFileVersion
     $Config.EnforceBehaviorPolicy = $Partner.Config.ServiceBehavior.EnforcePolicy
+    $Config.ForceAgentCleanup = $Partner.Config.ScriptBehavior.ForceAgentCleanup
 
     ### Function Body
     ###############################
@@ -2982,13 +2983,39 @@ function RemoveAgent {
     # Verify Removal was Successful
     DiagnoseAgent -NoLog -NoServerCheck
     if ($Agent.Health.Installed -eq $true) {
-        # Exit - Agent Removal Failed
-        FixServices -Restart
-        $Out = (
-            "MSI Removal of the existing " + $NC.Products.Agent.Name + " failed. " +
-            "Manual forcible removal is required for the Script to continue."
-        )
-        Log E 11 $Out -Exit
+
+        #If the forced removal of the agent is enabled
+        if ($Config.ForceAgentCleanup) {
+            $FAC = New-Object System.Diagnostics.ProcessStartInfo ($env:windir + "\system32\cmd.exe")
+            $FAC.UseShellExecute = $false
+            $FAC.CreateNoWindow = $true
+            $FAC.Arguments = ('/C "' + $Script.Path.AgentCleanup + '"')
+            # Run the forced cleanup
+            [System.Diagnostics.Process]::Start($FAC).WaitForExit() >$null
+
+            # Verify Removal was Successful again
+            DiagnoseAgent -NoLog -NoServerCheck
+
+            if ($Agent.Health.Installed -eq $true) {
+                # Exit - Agent Removal Failed
+                FixServices -Restart
+                $Out = (
+                    "Forced and MSI Removal of the existing " + $NC.Products.Agent.Name + " failed. " +
+                    "Manual forcible removal is required for the Script to continue."
+                )
+                Log E 11 $Out -Exit
+            }
+        } else {
+            # Exit - Agent Removal Failed
+            FixServices -Restart
+            $Out = (
+                "MSI Removal of the existing " + $NC.Products.Agent.Name + " failed. " +
+                "Manual forcible removal is required for the Script to continue."
+            )
+            Log E 11 $Out -Exit
+        }
+        # If forced removal successful, flag existing agent removal as true
+        $Install.ExistingAgentRemoved = $true
     }
     else
     { $Install.ExistingAgentRemoved = $true }

Agent/Lib/InstallAgent-Core.psm1

@@ -39,6 +39,8 @@ help@mymsp.com
     <!-- [REQUIRED - (1-60)] Amount of time (in minutes) to wait for the Windows Installer Service
   while another installation is in progress -->
     <InstallTimeoutPeriod>5</InstallTimeoutPeriod>    <!-- Default Value is 5 -->
+        <!-- [RECOMMENDED - (True)] - If there are issues with the MSI uninstall of the previous version, perform a cleanup -->
+  <ForceAgentCleanup>True</ForceAgentCleanup>
   </ScriptBehavior>
   <Server>
     <!-- [REQUIRED - (URL Without Protocol)] Your N-Central Server Address (get this from the