My Left Command key shows the desktop and can't be used for other functions

Hi Neumannannette,

I don't know if you've solved your problem, but I had exactly the same issue. What you have to do is go to mission control, where it says show desktop switch it to "left shift key" and then switch to whichever other key you want. This worked for me.

good luck

System Preferences>Keyboard>Shortcuts.

The "Show Desktop" shortcut is defined under the Mission Control section. The default is F11. You can set it to whatever you want. You apparently managed to change it to the left command key. The settings are user specific.

Try a restart.

Try booting into the Safe Mode using your normal account. Disconnect all peripherals except those needed for the test. Shut down the computer and then power it back up after waiting 10 seconds. Immediately after hearing the startup chime, hold down the shift key and continue to hold it until the gray Apple icon and a progress bar appear and again when you log in. The boot up is significantly slower than normal. This will reset some caches, forces a directory check, and disables all startup and login items, among other things. When you reboot normally, the initial reboot may be slower than normal. If the system operates normally, there may be 3rd party applications which are causing a problem. Try deleting/disabling the third party applications after a restart by using the application un-installer. For each disable/delete, you will need to restart if you don’t do them all at once.

Safe Mode - About

Safe Mode - Yosemite

Try unchecking this box.

NEUMANNANNETTE wrote:

Thanks for the reply, I knew that, and when I go to the mission control setting in keyboard shortcuts, it shows me F11 as the shortcut for showing the desktop. How can I change back to make F11 work, as it is shown, instead of the left command key...?

Try changing it to something else, then change it back. That may restore the setting.