If the HDD contains corrupted data, it will likely make the DVR lock up when it tries to access the disk to write further recordings.
To bypass the problem so that we can reformat the HDD, try the following.
Disconnect ALL the cameras from the DVR to prevent it from recording while we proceed further.
Force the DVR to restart by disconnecting and reconnecting its power supply.
Press the menu button to access the menu.
If the menu doesn't appear, you may have to manually switch the Display output between VGA and V-Out.
Once you have the main menu up, go to Device > HDD. Tick the box next to line one and press 'Format HDD'.
Then reconnect the cameras and hopefully the problem will be resolved.
A firmware update of your DVR might help prevent the problem from reoccurring.
I would recommend you to contact our tech support team to inquire as to whether a firmware update is available for your DVR.
When contacting the tech team, ensure that you provide us with the current system information of your DVR. Go into the main menu > System > Info. Look for the Firmware Version and the Hardware Version.
applies to DVR4-8-16 2600/2550 and 4-8 1200/1300 with VGA