At times, you may want to run SQL Server Management Studio as a different user than the AD account that you are logged into Windows. This command run from the command line will let you do just that (your path to the location of ssms.exe may be different). Change the domain\admin_user to the user you’d like to “run as”:
runas /noprofile /netonly /user:domain\admin_user “C:\Program Files (x86)\Microsoft SQL Server\100\Tools\Binn\VSShell\Common7\IDE\ssms.exe”
Note! If you are running this command locally, leave off the “/netonly” property – Thanks DCON!
Chris "Jake" Jacobsen 
#1 by Donal Conlon on January 6, 2010 - 6:21 pm
Now that is pretty handy.
#2 by adam on February 26, 2010 - 9:10 pm
has anyone had success with this? I have seen this on various posts but have not had any luck.
#3 by Jake on February 26, 2010 - 9:19 pm
What kind of errors are you seeing, Adam? Is the path to your instance of SQL correct?
#4 by Donal Conlon on July 28, 2010 - 5:57 pm
If you are using this to log on locally, leave off the “/netonly” property. Hoot!