Process proc = new Process();
System.Security.SecureString ssPwd = new System.Security.SecureString();

string password = "SomePassword";
for (int x = 0; x < password.Length; x++)
{
     ssPwd.AppendChar(password[x]);
}

ProcessStartInfo StartInfo = new ProcessStartInfo
{
   FileName = "Translink.exe",
   WorkingDirectory = @"C:Program FilesWestern UnionUniversal-Release",
   UserName = "someuser",
   Domain = "somedomain",
   Password = ssPwd,
   UseShellExecute = false,
   RedirectStandardOutput = true,
   RedirectStandardError = true
};
proc = Process.Start(StartInfo);
proc.WaitForExit();