This tool is able to present the SyncML protocol stream between the Windows client and management system. In addition it does some extra parsing to extract details and make the analyzing a bit easier.

The tool uses ETW to trace the MDM Sync session. In general the tool can be very handy to troubleshoot policy issues. Tracing what the client actually sends and receives provides deep protocol insights. Verifying OMA-URIs and data field definitions. It makes it easy to get confirmation about queried or applied settings.

SyncML Viewer download as zip archive can be found under subfolder SyncMLViewer/dist

Happy tracing!

The tool supports manual online updates. When a new version is available it will be indicated. Use Menu Item > Help > Check for SyncML Viewer Update to trigger a download.

I'm happy to take feedback. The easiest way is to create an issue here at the GitHub solution. The tool is far away from good developer coding practice :-), but for the small helper sufficient enough. I followed no design pattern like MVVM and all logic is in the code behind.

I have written an introduction blog article about the tool here:
https://oliverkieselbach.com/2019/10/11/windows-10-mdm-client-activity-monitoring-with-syncml-viewer


Credits:

Inspired by Michael Niehaus (@mniehaus) - blog about monitoring realtime MDM activity
https://oofhours.com/2019/07/25/want-to-watch-the-mdm-client-activity-in-real-time/

All possible due to Event Tracing for Windows (ETW)
https://docs.microsoft.com/en-us/windows/win32/etw/event-tracing-portal

Special thanks to Matt Graeber (@mattifestation) - for the published extended ETW Provider list
...without this info the tool wouldn't be possible for me to write!
https://gist.github.com/mattifestation/04e8299d8bc97ef825affe733310f7bd/

More MDM ETW Provider details
https://docs.microsoft.com/en-us/windows/client-management/mdm/diagnose-mdm-failures-in-windows-10

[MS-MDM]: Mobile Device Management Protocol
https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-mdm/

OMA DM protocol support - Get all the details how it is working...
https://docs.microsoft.com/en-us/windows/client-management/mdm/oma-dm-protocol-support

SyncML response status codes
https://docs.microsoft.com/en-us/windows/client-management/mdm/oma-dm-protocol-support#syncml-response-codes
http://openmobilealliance.org/release/Common/V1_2_2-20090724-A/OMA-TS-SyncML-RepPro-V1_2_2-20090724-A.pdf

UI Controls inspired by ILspy (https://github.com/icsharpcode/ILSpy) and the controls used there:

AvalonEdit
http://avalonedit.net/
released under MIT License (https://opensource.org/licenses/MIT)