Files Go - media player
No. The password reset process does not touch the hard drive. Your footage remains intact. Only a hardware CMOS reset (Part 6) maintains footage; a full "Factory Default" from the menu will erase settings but not video files.
Depending on your model and initial setup, you may have other recovery options available: longse dvr password reset link
If the automated tools fail, you can obtain a master code directly from the manufacturer. Provide your device's Model Number Serial Number Longse Technical Support longse dvr password reset link