Recently we have been testing Windows 10 20H2 Feature update deployment using ConfigMgr. When the update was applying it was failing and the error in software center was 0xC1900208.

To check what the code means I usually use the below Microsoft Doc but unfortunately the below code was not showing.
Windows Update error code list by component – Windows Deployment | Microsoft Docs
The error is listed under below Windows 10 upgrade errors doc
Get help with Windows 10 upgrade and installation errors (microsoft.com)

Since the error was relating to incompatible app next I checked the feature update logs these are located under a hidden folder on the root of the C drive C:\$WINDOWS.~BT\Sources\Panther
I checked the Setupact.log and the compatdata XML.
In the compatdata XML there was an incompatibility with the version of McAfee DLP installed on the device. This device was not getting the latest version of DLP.

To try fix the issue I updated the version to the latest release which support Windows 1020H2 and tried the update again but it continued to fail with a different error code 0x80240020.
To get the update to work correctly I had to remove the following folders
C:\Windows\ccmcache
C:\$WINDOWS.~BT\
And delete all the files and folders under
C:\Windows\SoftwareDistribution\Download
I also ran the below three action from the configuration manager agent in the control panel:
Machine policy retrieval and evaluation cycle, Software updates deployment evaluation cycle and software updates scan cycle.

I waited around 5 minutes for the scan’s to complete and tried the feature update again and it installed without issue this time.