Hi, @MJ
Thank you for posting in Microsoft Q&A forum.
To find the Configuration Manager clients that require a reboot, you can use the SCCM console. Here are the steps to follow:
Launch the SCCM console and navigate to Assets and Compliance \ Overview \ Devices.
Right-click on the Menu bar and add a new column for Pending Restart.
The Pending Restart column will show why the device need a reboot, if the Pending Restart column show "No", it does not need a reboot.
Once you have identified the devices that require a restart, you can use a client notification action to restart those client devices.
For the status "Error," you can refer to the error message and take appropriate action.
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