What can cause Explorer to consume >50% CPU for extended periods?

mmo said:

What I meant to say with "that's not explorer" is that I *do* see programs that cause disk activity like e.g. SearchIndexer but Explorer is not among the top users during such phases.

Consider using Process Explorer: https://docs.microsoft.com/en-us/sys...ocess-explorer from Microsoft website.

First sort by CPU usage in the main view shown in the 1st screenshot.

Double-click on the suspicious process with high CPU usage to look at the Performance Graph tab and look at the CPU usage graph.

The second screenshot in the link is from clicking the small CPU usage graph from the 1st screenshot.

This is a portable app and does not need to be "installed" to run it. Just unzip the downloaded zip and right-click procexp64.exe and run as administrator.

@mmo - I'm wondering when you're going to post illustrative screenshots... Thanks.