Windows (not just File Explorer) hangs up deleting or moving files

I've run searches but can't find my specific problem, and it's driving me nuts.

I'm having trouble moving and deleting files in Windows -- not just File Explorer, but in FreeCommander, as well.

There are times when Windows cooperates fully, but sometimes it stalls when moving (click-and-drag OR cut-and-paste) or deleting files. It doesn't seem to matter whether it's a single file or multiples, and when it's hanging up it does the same thing in FreeCommander as in File Explorer, which tells me that the problem isn't in either of these programs. I get the little popup that indicates movement or deletion, but the graph is blank and Windows reports that it is "calculating." This has gone for up to three minutes (I actually timed it) before I shut down the program in question in Task Manager.

I can't predict when it's going to start doing this, when it will stop, or what's holding it up when it's happening. Even a hard boot won't change it.

Any help would be appreciated.

I've gone over this every which way, trying every possible trick I can find on the web, but nothing makes the least bit of difference. As noted, it's intermittent, and using a different file management program doesn't help. Disabling Avast didn't help, and neither did uninstalling it. I ran a thorough scan with Avast and Malwarebytes, but neither turned up any problems. The drive in question doesn't even matter; it happens with my main data/D drive, and also on an extra/E drive I use in a hot-swap dock when needed.

Does anyone have any other ideas?