SendKeys.SendWait is not working in save as dialog for external exe in wpf

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C#

WPF

Hi,

I have launched a external exe file which is running successfully, but the problem is I need to save the file automatically.
Following source code I have added, but it is not working:

"SendKeys.SendWait("%P");
SendKeys.SendWait("{Enter}");

SendKeys.SendWait("^%s?");
Thread.Sleep(5000);
SetForegroundWindow(FindWindow(null, "Save As"));
Thread.Sleep(5000);
SendKeys.SendWait("abc");"

Here Save As dialog box will appear but the message will not appear.
Kindly help me on this to resolve.

Thanks