Enabling Fast User Switching 10.10


Hi everyone,

This seems to be very hit and miss on Yosemite. Traditionally, we enable fast users in Managed Preferences.

User level enforced
Domain : .GlobalPreferences
Key: MultipleSessionEnabled
Value: True

This works perfectly on 10.9 and below. 10.10 seems to have problems with user level enforced mcx, sometimes it applies, sometimes it doesn't.

How is everyone else managing fast user switching in yosemite?

I have tried defaults write /Library/Preferences/.GlobalPreferences MultipleSessionEnabled -bool 'YES'
which doesn't seem to work either.

I have also tried a custom setting via configuration profile but no luck with that also.

Any ideas?


Valued Contributor
defaults write /Library/Preferences/.GlobalPreferences MultipleSessionEnabled -bool Yes

defaults write /Library/Preferences/com.apple.loginwindow SHOWFULLNAME -bool YES

This has always worked for me, maybe it could be the extra apostrophes? I use this during imagining at reboot, but this could be used as a policy as well (test it out!).


I have deployed

defaults write /Library/Preferences/.GlobalPreferences MultipleSessionEnabled -bool 'YES'

successfully to 10.10.2 and 10.10.3 clients via policy.


Hi guys,

cheers for the responses. This does seem to work on any new accounts, but it doesn't seem to affect any existing users.

Contributor II

Have you tried:

defaults write /Users/*/Library/Preferences/.GlobalPreferences MultipleSessionEnabled -bool 'YES'

Esteemed Contributor
Esteemed Contributor

Just to add. User level MCX & Yosemite seems to not work.

There are a few threads in that here, so might me time to move to profiles.


Hi Ben,

This is what I am seeing. I tried a custom configuration profile for fast user switching and couldn't get it working. I could only get it to deploy at a system level. I'll see if the threads here can shed any more light.

Contributor II

@jamesdurler Hi James, did you ever find something reliable to deploy at the system level?

New Contributor III

I know this is an old thread but anyone managed to get this to work on 10.14? Thanks

New Contributor III

Hi @j.tanudjaja ,

It works for Mojave, but you need to add .plist in your command line:

defaults write /Library/Preferences/.GlobalPreferences.plist MultipleSessionEnabled -bool true
defaults write /Library/Preferences/com.apple.loginwindow.plist SHOWFULLNAME -bool true

New Contributor III

In case anyone else is having the same issue with Monterey go to this article - https://www.kevinmcox.com/2022/04/adventures-in-fast-user-switching-on-macos-monterey/

Below is the script I deployed through JAMF. The key is running the last 2 plist settings AS the user.


# Get current logged in user
currentuser=`/bin/ls -la /dev/console | /usr/bin/cut -d " " -f 4`

# Global Setting. Enables for all users.
defaults write /Library/Preferences/.GlobalPreferences MultipleSessionEnabled -bool true

# User Specific Setting. Note - if running manually use SUDO
# UserSwitcher - Where you want the fast user switching icon to appear
# OPTIONS: 1 = Show in Control Center. (WE USE #2) 2 = Show in Menu Bar. 3 = Show in both. 8 = Hidden (FUS disabled)
su $currentuser -c "defaults -currentHost write com.apple.controlcenter UserSwitcher -int 2"

# User Specific Setting. Note - if running manually use SUDO
# userMenuExtraStyle - What you want it to display.
# OPTIONS: 0 = Full Name. (WE USE #1) 1 = Account Name (username). 2 = Icon (default)
su $currentuser -c "defaults write .GlobalPreferences userMenuExtraStyle -int 1"

New Contributor III

# Global Setting. Enables for all users.
defaults write /Library/Preferences/.GlobalPreferences MultipleSessionEnabled -bool true

but this doesn't add the option for all users, If a new user logs in the complete script needs to be ran.

Is there one that will effect all users and not just current console user?