When things go wrong...

Reading Logs

https://learn.microsoft.com/en-us/intune/configmgr/core/support/support-center is another great tool for troubleshooting clients.
Here’s the quickstart guide for that https://learn.microsoft.com/en-us/intune/configmgr/core/support/support-center-quickstart

The CMTrace log viewing tool is automatically installed along with the Configuration Manager client and makes it easier to read .log files. It's added to the client installation directory, which by default is %WinDir%\ccm\cmtrace.exe. Simply run the executable, there's no need to "install" it and if desired you can associate it with .log files.

CMTrace Tips:

• Lookup up error codes:
  Click on Tools | Error Lookup (or use CTRL-L). Type in an error code and then click Lookup to display more information about the error.
  
  

  

  
  
  

• Merge Logs:
  You can view multiple logs in the same window. This is useful when troubleshooting with multiple logs that have overlapping time frames. Click on File | Open and select multiple logs, then check the box for "Merge selected files" before you click Open.
  
  

  

  
  
  

• Highlighting:
  Click on Tools | Highlight. This will highlight lines that contain the specified text. By default, any line that contains "error" or "fail" will already be highlighted in red.
  
  

  

Remotely reading logs

Use this sparingly as it does take up more space in the DB.
You can right click on a device, then go to Client Diagnostics and Collect Client Logs

Assuming the client is online, after a few minutes you will be able to view the logs. Open Resource Explorer to access the collected logs.

Find Diagnostic Files and on the right side you should see what you just collected. Double click on it to open them.

You'll then have access to all the CM related logs.

Client Installation

• If the client was pushed out (installed) but you can't find the applet in the control panel or policies do not appear to be assigned, review the installation logs to search for errors that might help determine the issue.

  Installation logs location:

  C:\Windows\CCMSetup\Logs

General Operation

• Review operational logs

  Operational logs location:

  C:\Windows\CCM\Logs

  For log description information see the https://learn.microsoft.com/en-us/intune/configmgr/core/plan-design/hierarchy/log-files

• Review Windows Event logs
  log=Application log, source=Configuration Manager Agent

Removal

• Uninstall an existing Configuration Manager client:
   
  

  • Run this command from an elevated prompt:

    c:\Windows\CCMSetup\ccmsetup.exe /uninstall

     

  • Ensure the following registry keys no longer exist following the uninstall. Manually remove them if necessary:

    Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\CCM Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\CCMSetup Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SMS

  • Ensure the following directories no longer exist following the uninstall. Manually remove them if necessary:

    C:\Windows\CCMSetup C:\Windows\CCMcache C:\Windows\CCM