I can see why this is confusing, David B,
What you describe sounds like Windows is unexpectedly showing/focusing the desktop. Since it happens with multiple applications, this might link to hardware or input issue. If you have another mouse, it'd be best to test:
- Temporarily disconnect your current mouse and use a different mouse.
- If the problem stops, that points toward the mouse or its input.
- If it still happens, the problem is with the system itself.
Task Manager not showing anything unusual does not completely rule out a background program or service. Besides the checks above, I have a few other suggestions here that you should consider:
1 - Confirm whether this is specific to your current Windows profile
- Open Settings > Accounts > create a temporary local account
- Sign out of your current one and sign into the new profile
- Use your mouse and see if the behavior repeats there.
2 - Reconfirm no hotkeys happen
- Press Win + Ctrl + O to turn on the on-screen keyboard
- If it's not enabled, open Settings > Accessibility > Keyboard > turn it on there
- Use your mouse normally and confirm no keys were registered when the behavior appears.
3 - Turn off the Show Desktop button (if it's enabled)
- Open Settings > Personalization > Taskbar > Taskbar behaviors
- Uncheck Select the far corner of the taskbar to show the desktop
4 - Rule out third-party interventions
- Press Win + R > type
msconfig> press Enter - Go to Services > Check Hide all Microsoft services > Disable all
- Go to Startup to open Task Manager > Disable all items > Restart your PC.
Use the computer normally and see whether a click still suddenly sends you to the desktop. If the problem is gone, it's likely that one of the disabled was the cause. You may need to manually enable them half-by-half to identify the offender, then consider removing or disabling it.
Disclaimer: A "clean boot" starts Windows with a minimal set of drivers and startup programs. It helps to determine whether a background service is interfering with your game or program and to isolate the cause of a problem. They might look complicated at first glance but can help you get back on track. To avoid any trouble, please follow them in order and step-by-step. Refer to How to perform a clean boot in Windows - Microsoft Support
5 - Repair the Windows system files
- Open Command Prompt as Administrator
- Run
dism /Online /Cleanup-Image /RestoreHealth - When it finishes, run
sfc /scannow> restart your PC.
In the meantime, I can suggest checks for malware too, but I can't say for sure it's a cause yet. You can open Windows Security > Virus & threat protection > Scan options, and run a Full scan.
Also, there is one detail that I'm not entirely certain: if you're opening multiple applications/services, does the desktop appear over them, or only one current window minimized to the taskbar?