Apparently there's no such thing as echo.exe, it's a part of cmd.exe

Password Manager/PasswordGenerator.cs

@@ -40,8 +40,8 @@ namespace Password_Generator
                 {
                     StartInfo = new ProcessStartInfo
                     {
-                        FileName = "echo", //TODO: pipe the return value of RandomStr to gpg with the --quiet --encrypt --recipient {recipient} flags
+                        FileName = "cmd.exe", //TODO: pipe the return value of RandomStr to gpg with the --quiet --encrypt --recipient {recipient} flags
-                        Arguments = $"{RandomStr(length, no_symbols)} | gpg --quiet --encrypt --recipient {recipient}",
+                        Arguments = $"echo {RandomStr(length, no_symbols)} | gpg --quiet --encrypt --recipient {recipient}",
                         UseShellExecute = false,
                         RedirectStandardOutput = true,
                         CreateNoWindow = true