Hi, I am using Windows 10 Pro 20H2, 19042.804. There is a watermark showing "Testing Mode, Windows 10 Pro ..." on desktop. It seems that this watermark is displayed if a driver or a program is not digitally signed by Microsoft. In order to determine which driver is not signed, I used sigverif. It found 340 driver. 339 driver is signed by Microsoft and 1 driver (wdfcoinstaller01011) is not installed. I also used dxdiag and verified that display and sound card drivers are signed. In addition to that, I used Driver Verifier Manager (verifier) and ıt did not found any unsigned driver. I am wondering what might cause "testing mode" watermark to be displayed if there is not any unsigned driver? Could you help me in this regard? P.S.: My native language is not English.