Cannot bring some apps to the front

This started this morning. Running Windows 10 Pro. I can run the browser (Chrome), luckily. Word also. But I cannot most other apps (I think), like WinSCP, but not Calc, not Notepad++, not Notepad. If I try to run Calc, it loads in the task try and if I hover the mouse over it I can see the image of it. Same with Notepad++, But if I click on the icon, nothing happens. Word is fine when loading or clicking on the task try icon. Same with Chrome. Same with Edge, Firefox, Visual Studio. So far, limited to Notepad, Notepad++ and Calc but there could be more.

More: Explorer as well.

WELL, not exactly. I use a program called Agent Ransack to search the desktop. I don't use it much but I know that you can click on an Explorer icon and choose the folders you want to search. I did that and explorer came up OK. BUT not from the Start Menu or task bar.

Unfortunately running Explorer from this program limits me to selecting folders.

Switch to and bring to the front in Task Mgr does nothing.

If I run Word and then File->Open-Browse, I can use Explorer no problem. Just not from Start or Task Bar.

Rebooted: Yes
Anti-Malware: Windows Defender
Alt-Tab/win-key tab: While Explorer is on the Task Tray at the bottom of the screen it does not appear in Win-key tab selection.
Those apps which have an Open Location menu choice, I can select it and while that opens explorer, explorer is still just in the task tray.

Running MalwareBytes now.

I have another problem which I noted here and thought was solved but isn't: My mouse pointer is "unstable" in that at times it works as usual but frequently it disappears. There is no pointer at all. I can alt-tab around, etc., and eventually it comes back.

I ran MalwareBytes which found on PUP which I quarantined. Rebooted. No change. Explorer still cannot come to the front. In the task bar I can click "restore" or "maximize" but nothing happens. I can live without Calc but not without Explorer.

Task bar is at the bottom. Not sure about the search helper. My program (I'm a programmer) opens Explorer from a File Open dialog box, probably like most programs do. While Explorer runs there is no window on the desktop that I can access. Same with Calc. So far, only those two.