Automated remediation of user-created public M365 groups

Author: Xorlent

Fix-PublicM365Groups.ps1

@@ -0,0 +1,47 @@
+$ConfigFile = $PWD.Path + '\O365Monitor-Config.xml'
+$xml = New-Object System.Xml.XmlDocument
+$xml.Load($ConfigFile)
+$ConfigParams = $xml.SelectSingleNode("//o365app")
+
+$LogFile = $PWD.Path + '\O365Montior-PublicGroups.csv'
+
+# Initialize configuration variables from config xml file
+$TenantID = $ConfigParams.SelectSingleNode("tenantid").InnerText
+$APPObjectID = $ConfigParams.SelectSingleNode("appid").InnerText
+
+Connect-MgGraph -ClientId $APPObjectID -TenantId $TenantID -CertificateName "CN=O365Monitor" -ErrorAction SilentlyContinue -Errorvariable ConnectionError | Out-Null
+
+if($ConnectionError -ne $null)
+    {
+    Write-Host "$ConnectionError" -Foregroundcolor Red
+    Exit
+    }
+
+if (Test-Path -Path $LogFile -PathType Leaf){
+    rm $LogFile
+}
+
+$NotificationFlag = 0
+$Headers = '"ID","Group Name","Group Description"'
+$GroupList = Get-MgGroup -Filter "groupTypes/any(c:c eq 'Unified')" -All
+$PublicGroupList = $GroupList | Where-Object -Property Visibility -eq "Public"
+
+Add-Content $LogFile $Headers
+
+foreach ($Group in $PublicGroupList)
+{
+    Update-MgGroup -GroupId $Group.Id -Visibility "Private"
+    Write-Host -NoNewLine "."
+    $Entry = '"' + $Group.Id + '","' + $Group.DisplayName + '","' + $Group.Description + '"'
+    Add-Content $LogFile $Entry
+    $NotificationFlag++
+}
+
+if($NotificationFlag){
+    Write-Output "Results can be found in $LogFile"
+}
+else{
+    Write-Output "Congratulations, no public M365 groups found."
+}
+
+Disconnect-MgGraph | Out-Null