RUNAS (Windows 2000/XP)

Execute a program under a different user account.

Syntax
      RUNAS [/profile] [/env] [/netonly] /user:user Program

Key
   /profile   Option to load the user's profile (registry)
   /env       Use current environment instead of user's.
   /netonly   Use if the credentials specified are for RAS only.
   /user      Username in form USER@DOMAIN or DOMAIN\USER
              (USER@DOMAIN is not compatible with /netonly)
   Program    The command to execute

Examples:
   runas /profile /user:mymachine\administrator CMD
   runas /profile /env /user:SCOT_DOMAIN\administrator NOTEPAD
   runas /env /user:jDoe@swest.ss64.com "NOTEPAD \"my file.txt\""

Enter the password when prompted.

RunAs from the Windows explorer GUI
Select an executable file, Shift-Right-click and select Run As..
This option can be hidden by setting
HKLM\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer
HideRunAsVerb=1

ErrorLevel
The error level returned by RunAs is not consistent between operating systems

In Windows 2000:
- success: %ERRORLEVEL%=1
- fails: %ERRORLEVEL%=0

In Windows XP:
- success: %ERRORLEVEL%=0
- fails: %ERRORLEVEL%=1

For Example

 VER | find "2000" > nul
 IF %errorlevel% EQU 0 GOTO s_2000
   
 ::Running XP
 RUNAS /user:jDoe@swest.ss64.com "mycommand.exe"
 IF %ERRORLEVEL%==0 Echo command succeeded
 goto :eof
   
 :s_2000
 ::Running Windows 2000
 RUNAS /user:jDoe@swest.ss64.com "mycommand.exe"
 IF %ERRORLEVEL%==1 Echo command succeeded
 goto :eof

RunAs Reqires the "Secondary Logon" service to be running.

"Our deepest fear is not that we are inadequate. Our deepest fear is that we are powerful beyond measure. It is our light, not our darkness, that most frightens us" - Nelson Mandela

Related Commands:

AT - Run a command on a remote machine (at a scheduled time)
Aaron Margosis - Running with least privilege
joeware.net - CPAU (Create Process As User) like RunAs but with an options to encrypt the password.
PsExec - Execute process remotely

Equivalent Linux BASH commands:

SU - Switch User