If the DVR is older, or if you bought it used, the previous owner may have never set a complex password. Try these factory defaults before tearing your hair out:
If you don't have access to the web interface or prefer to use the DVR's menu, follow these steps: hi sharp dvr reset password
Before performing a full reset, check if your DVR is still using its factory settings. Many Hi Sharp units ship with these standard credentials: admin Password: 123456 or admin If the DVR is older, or if you