Hello,
It’s possible that the March Cumulative update has caused compatibility issues with Sync Center. Microsoft has not officially announced the end of life for Sync Center, so it is still supposed to be supported.
Here are some steps you can take to try to check the issue:
Check Event Viewer: Open Event Viewer and check the logs for any related error messages or warnings that could indicate what might be causing the issue.
Reset Offline Files: Open the Sync Center and click on Manage Offline Files on the left pane. Click on Disable Offline Files and restart the system. After the system is restarted, go back to the same setting and Enable Offline Files.
Uninstall Update: Uninstall the March Cumulative update, restart the system, and check if sync center could work.
You said that the latest March Cumulative update has been installed, because you didn't provide the update number, I also suggest that check the update history below to find if any new update could be found and installed.
March 12, 2024—KB5035845 (OS Builds 19044.4170 and 19045.4170) - Microsoft Support
Best Regards,
Hania Lian
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