How to close all open windows at once?

Easiest way I've found, sorry if someone already posted...

Go to task bar settings and set "Combine taskbar buttons" to "When taskbar is full". Right click on the group and click "Close all windows". Revert "Combine..." back to "Never".

Voilà

I just found myself a quick way of doing this after a very long overtime work today.

Win10 user here:

+ Tab ( Will bring up something like Win Aero )

then

Press Delete until every window on your display is gone.

Sadly, if you have multi monitor/display, I don't know how to Delete/close the other windows yet.

For closing all windows of a program by using only the keyboard:

windows button > esc > tab > right arrow till you reach desired program > right-mouse button > arrow up > enter

Note: This only works when 'always combine' is selected in the taskbar options and your keyboard has a right-click mouse button, usually somewhere next to the spacebar

You can use the command line utility NirCmd (freeware) (archive.org's mirror for the webpage; archive.org's mirror for the binary) and execute:

nircmd.exe win close alltopnodesktop

I use it on Windows 10 Enterprise x64 version 1709, and it works as intended: it will close all windows.

The program is supposed to work on Windows 9x/ME, Windows NT, Windows 2000, Windows XP, Windows Server 2003, Windows Vista, Windows Server 2008, Windows 7, Windows 8, and Windows 10.

quickly click ALT+F4 many times :)
p.s. But till that, all windows should be active, for that click ALT+TAB.

Powershell command: Get-Process | Where-Object {$_.MainWindowTitle -ne ""} | stop-process

I got this from another SO answer here https://stackoverflow.com/questions/9725629/how-to-close-all-windows

I like to see my open windows ungrouped, but realized that this i.e. closing multiple windows at once was a problem with such a setting. A less time-taking method would be to use the command line like this :

taskkill /im explorer.exe -f

And then restart explorer using :

explorer

Caution : This will cause processes like file copying on the default Windows interface to abort.

After doing Ctrl-Shift-Esc, go to applications. Then, press shift down and end task, all of them will end (You might get a confirmation message or something depending on the program).

Sometimes, even when you close a program, the processes of the program (The biggest example is an unclosed connection to a local file) may still be on your computer. Most of the time, these processes are mainly overlooked by the owner software because they use almost no space. However, if you still want to end them, just to be meticulous, go to processes and you'll have to end them one by one.

It's not a one-click solution but it is the fastest I know with my Windows 7 Pro

1. Open taskbar properties (right click > properties) or (Control Panel > Appearance and Personalization > Taskbar and Start Menu)
2. Select "Group similar taskbar buttons" = "Group similar taskbar buttons", and click OK
3. Your windows are now grouped, right-click and select "Close all windows"
4. Go back to taskbar properties to restore your old settings

I usually (yes, this happens a lot to me..) just press Alt key and then go crazy on the F4 key until everything is shut down. Not one click, but it's pretty fast. Or, depending on your system, reboot.. Don't forget to save anything.

Or maybe you could simply switch users to continue your work without all these tabs. Then when you're down, shutting down the computer will kill all the processes for the first user...

Not the best solutions, I just thought Id give this one a try.

All answers I could quickly find on this topic involve either the tip Molly gave or using an application (or coding it yourself). For example (I haven't tried this), Close All Windows.

Also, by pressing Ctrl + Shift + Esc you get the Windows Task Manager, where you can see all running applications at once (among other things), select them, and End Task them.

Simultaneously close all open windows:

1. While pressing the Ctrl key, successively click each of the task icons on the taskbar.
2. Right-click the last task icon, and choose Close Group.

If you only want to minimize the windows, use the 'Show Desktop' shorcut.