programmatically run cmd.exe as administrator in vista, C#

Try executing the runas command:

...

using System.Diagnostics;

...

string UserName = "user name goes here";
ProcessStartInfo p1 = new ProcessStartInfo();
  p1.FileName = "runas";
  p1.Arguments = String.Format("/env /u:{0} cmd", UserName);
Process.Start(p1);

...

(And I don't think you need an explicit UseShellExecute)

Just Try this, This worked for Me.

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using System.Diagnostics;

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ProcessStartInfo startInfo = new ProcessStartInfo();
  startInfo.UseShellExecute = true;            
  startInfo.Verb = "runas";
  startInfo.Arguments = "/env /user:" + "Administrator" + " cmd";
Process.Start(startInfo);

...

Ashutosh