Run as Different User option is Missing in Windows Vista

Solution:

Mark Russinovich and Jon Schwartz at   Sysinternals developed  a small utility named as Shell Run As  which will enable the option on windows vista .

This tool adds the option to start an application with a different users credentials from the GUI

This is a command line Utility that allows to register the GUI short cuts with the following options

Usage: shellrunas [/reg | [/quietreg ] | /regnetonly [/quiet] | unreg | [/netonly] <program> <arguments>

/reg                    Registers ShellRunas shell context-menu entry

/regnetonly      Registers Shell /netonly context-menu entry

Note: a command prompt will flash when the program starts

/unreg              Unregisters ShellRunas shell context-menu entry

/quiet               Register or unregisters ShellRunas shell context-menu entry without result dialog

/netonly          Use if specified credentials are for remote access only

<program>     Runs program with specified credentials and parameters

You have to download the file  from the sysinternals website and palce it on C drive.

Open CMD and register the utility as shown below

After Registering the file you will be able to get the Run as Different user option by selecting the shortcut of the application holding the shift key and right click

 You can Download Shell Run As from technet.microsoft.com/en-us/sysinternals