Pass Login Enter Password to an external application. C# with Windows Forms

Question

I used the code passed in

Write program in another’s textbox

To write login/password in another manufacturer’s program.

I did so:

Process processo = Process.Start(@"C:\Program Files (x86)\ZKTeco\ZKAccess3.5\Access.exe");
IntPtr h = processo.MainWindowHandle;
SetForegroundWindow(h);
processo.WaitForInputIdle(); // Isso aqui foi de extrema importância :D.

SendKeys.SendWait("admin");
SendKeys.SendWait("{TAB}");
SendKeys.SendWait("admin");
SendKeys.SendWait("{ENTER}");

It even calls the system, but does not pass the values to the respective fields.