"Switch User" option missing in Windows Vista

Issue: "Switch User" option missing in Windows Vista, what do I do?

Solution:

1. Open Notebpad, and copy paste below said script.

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System]
"HideFastUserSwitching"=-

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System]
"HideFastUserSwitching"=-

Now save the file as Fix.reg, then double click fix.reg file and merge it to the registry.

Then restart the computer.

I hope it will help :)