C#: Load roaming profile and execute program as user

public static Process Start(
   string fileName,
   string arguments,
   string userName,
   SecureString password,
   string domain
)

Process p = new Process();

        p.StartInfo.FileName = textFilename.Text;
        p.StartInfo.Arguments = textArgument.Text;
        p.StartInfo.UserName = textUsername.Text;
        p.StartInfo.Domain = textDomain.Text;
        p.StartInfo.Password = securePassword.SecureText;

        p.StartInfo.LoadUserProfile = true;
        p.StartInfo.UseShellExecute = false;

        try {
            p.Start();
        } catch (Win32Exception ex) {
            MessageBox.Show("Error:rn" + ex.Message);
        }