⤷ Disable/enable taskbar

Taskbar window name is 'Shell_TrayWnd'. Use FindWindow function to find Taskbar handle, and EnableWindow function to disable/enable taskbar.
For example:

var
  TaskbarHandle: THandle;
...

procedure TForm1.FormCreate(Sender: TObject);
begin
  TaskbarHandle:=FindWindow('Shell_TrayWnd', nil);
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  EnableWindow(TaskbarHandle, False);
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
  EnableWindow(TaskbarHandle, True);
end;
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