diff --git a/Modules/CIPPCore/Public/Entrypoints/HTTP Functions/Email-Exchange/Reports/Invoke-ListOutdatedActiveSyncDevices.ps1 b/Modules/CIPPCore/Public/Entrypoints/HTTP Functions/Email-Exchange/Reports/Invoke-ListOutdatedActiveSyncDevices.ps1
new file mode 100644
index 000000000000..e0bf7019a3e7
--- /dev/null
+++ b/Modules/CIPPCore/Public/Entrypoints/HTTP Functions/Email-Exchange/Reports/Invoke-ListOutdatedActiveSyncDevices.ps1	
@@ -0,0 +1,60 @@
+function Invoke-ListOutdatedActiveSyncDevices {
+    <#
+    .FUNCTIONALITY
+        Entrypoint
+    .ROLE
+        Exchange.Mailbox.Read
+    #>
+    [CmdletBinding()]
+    param($Request, $TriggerMetadata)
+    
+    # Interact with query parameters or the body of the request.
+    $TenantFilter = $Request.Query.TenantFilter
+    
+    try {
+        # Filter for outdated ActiveSync devices (version < 16.1) using the ActiveSync switch
+        # ActiveSync 16.1 was released in June 2016 and will be the minimum required version starting March 1, 2026
+        # Using the -ActiveSync switch to filter on the Exchange server for better performance
+        
+        # Get mobile devices with ActiveSync filter
+        $AllDevices = New-ExoRequest -tenantid $TenantFilter -cmdlet 'Get-MobileDevice' -cmdParams @{ActiveSync = $true}
+        
+        $MinimumVersion = [version]'16.1'
+        
+        # Client-side filtering for version comparison (as version comparison is not supported in OPATH)
+        $OutdatedDevices = $AllDevices | Where-Object {
+            # Ensure ClientVersion exists and can be parsed
+            if (-not $_.ClientVersion) {
+                return $false
+            }
+            # Safely parse and check if version is less than 16.1
+            try {
+                $deviceVersion = [version]$_.ClientVersion
+                return ($deviceVersion -lt $MinimumVersion)
+            } catch {
+                # If version parsing fails, exclude the device
+                return $false
+            }
+        } | Sort-Object UserDisplayName | Select-Object @{ Name = 'userDisplayName'; Expression = { $_.UserDisplayName } },
+        @{ Name = 'userPrincipalName'; Expression = { $_.UserPrincipalName } },
+        @{ Name = 'deviceId'; Expression = { $_.DeviceId } },
+        @{ Name = 'deviceModel'; Expression = { $_.DeviceModel } },
+        @{ Name = 'clientType'; Expression = { $_.ClientType } },
+        @{ Name = 'clientVersion'; Expression = { $_.ClientVersion } },
+        @{ Name = 'deviceOS'; Expression = { $_.DeviceOS } },
+        @{ Name = 'deviceFriendlyName'; Expression = { if ([string]::IsNullOrEmpty($_.DeviceFriendlyName)) { 'Unknown' } else { $_.DeviceFriendlyName } } },
+        @{ Name = 'firstSyncTime'; Expression = { $_.FirstSyncTime } },
+        @{ Name = 'lastSuccessSync'; Expression = { $_.LastSuccessSync } }
+        
+        $StatusCode = [HttpStatusCode]::OK
+    } catch {
+        $ErrorMessage = Get-NormalizedError -Message $_.Exception.Message
+        $StatusCode = [HttpStatusCode]::Forbidden
+        $OutdatedDevices = $ErrorMessage
+    }
+    
+    return ([HttpResponseContext]@{
+            StatusCode = $StatusCode
+            Body       = @($OutdatedDevices)
+        })
+}