A change made on McAfee's license servers on August 27, 2021, resulted in the McAfee Agent on some client systems getting an incorrect status. The incorrect status causes their update task to fail when updating from McAfee Enterprise managed repositories.
Agents not managed by any ePO solution need to be manually remediated by uninstalling and reinstalling the agent. A tool to do this is provided in the link above.
Download the zip file, then extract and run the required 64bit(x64) or 32bit(x86) tool.