I noticed my new HP laptop systems came with the SWITCH USER option disabled, and I could not find any Control Panel settings to toggle it back on. After much research, this is the only way I found available to turn it back on.
How to enable / disable the “Switch User” aka ‘Fast User Switching’
option in Windows 7 using the Windows Registry Editor:
This is the steps necessary to enable or disable the “Switch User” option in Windows 7:
1. Type regedit into the RUN or Start Menu Searchbox and press Enter. This will launch the Registry Editor window/program.
2. Navigate to the following registry key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System
3. In the right-side pane of the Registry Editor, find the key/value pair “HideFastUserSwitching” and set its value to 1 [to disable] OR 0 [to Enable]. If the key/value pair “HideFastUserSwitching” is not listed under the SYSTEM key, then create it as a new DWORD.
4. With your next system reboot, the “Switch User” option will be enabled/disabled from the Welcome screen and from the Shutdown menu.
NOTE:
If you have made the registry change I outlined in this article (AND you have logged out & rebooted) and Fast User Switching STILL does not appear, perhaps it is one of the following issues:
– Fast User Switching will not appear if it has not been turned on in User Accounts in Control Panel
– Fast User Switching is not available on computers that are members of a network domain
– Only users with a computer administrator account on a computer can turn on or turn off Fast User Switching
E-RazorHead 
Thank You so much. For some reason my switch user just stopped working and your solution s the ONLY solution that worked. THANKS.
The link provided hare has asmall mistake. The correct link is HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System
Thanks! Updated the article accordingly…
fast switch user can not appear when the user is logged on, why?
please help me…!!!
If you have made the registry change I outlined in this article (AND you have logged out & rebooted) and Fast User Switching STILL does not appear, perhaps it is one of the following issues:
– Fast User Switching will not appear if it has not been turned on in User Accounts in Control Panel
– Fast User Switching is not available on computers that are members of a network domain
– Only users with a computer administrator account on a computer can turn on or turn off Fast User Switching
when i try to change the binary, a dialogue pops up saying “Cannot edit HideFastUserSwitching: Error writing the value’s new contents.” Help? i need fast user switching so i don’t have to close all of my in-progress schoolwork when my mom needs to use the laptop.