Why Multiple explorer.exe processes running?

Win 10 Pro 64bit. From time to time I see 2 or more explorer.exe processes running (viewed via task manager). The owner of them is me. I have no idea when or why they get started. I have been taking note of the PID of the first explorer process after starting my system. Then if I see more than one I just kill the others. I've experienced no issues after killing the extras.

Is it normal to have multiple explorer.exe processes running? What they might be used for?

Is there a way to see the process tree (parents, children, etc.)?

Thanks,
Larry

There will always be at least one running, and that's the default desktop shell. That's what displays the taskbar, icons on the desktop, and start menu.

When you open one instance of File Explorer, then you will see two instances. Open another and there will be three, etc...

Unless you are talking about Internet Explorer (which is iexplorer.exe) in which case one instance is opened per tab you have open, plus an instance for the UI Shell.

I'm talking about explorer.exe, not iexplorer. I find that no more explorer.exe processes come into existence when I start one or more File explorers.
-- Larry

That's strange. There's a setting under Folder Options->View->Launch Folders in a separate process which defaults to on. This setting should make each new explorer window open in a separate process, but doesn't seem to do that anymore.

Win10 (at least mine) does not have Folder Options. It has File Explorer Options (which looks a whole lot like Folder Options from Win7).
Under the View tab there is an option to launch folder windows in a separate process. That option is not checked.

-- Larry

Win10 (at least mine) does not have Folder Options. It has File Explorer Options (which looks a whole lot like Folder Options from Win7).
Under the View tab there is an option to launch folder windows in a separate process. That option is not checked.

Notice the name of the dialog, it says "Folder Options". The default is for that to be checked. It doesn't seem to do anything either way.

Is there a way to see the process tree (parents, children, etc.)?

Process Hacker or Process Monitor

There are 2 options to run multiple explorer, one can be done only via reg, maybe enabled by some software?

All instances of Windows Explorer run in one process and the Desktop and Taskbar run in a separate process
reg add "HKCUSoftwareMicrosoftWindowsCurrentVersionExplorer" /v "DesktopProcess" /t REG_DWORD /d "1" /f

Launch folder windows in a separate process
reg add "HKCUSoftwareMicrosoftWindowsCurrentVersionExplorerAdvanced" /v "SeparateProcess" /t REG_DWORD /d "1" /f

I see second , when I open Control Panel, when file explorer is opened, it keeps it opened for some time.

 

Notice the name of the dialog, it says "Folder Options". The default is for that to be checked. It doesn't seem to do anything either way.

Here is what my Win10 Pro system has:

If I search for "Folder", File Explorer Options is what shows up. Interesting that the same OS looks different in different installations, but that doesn't have much to do with the original issue!
--Larry