How to fix this error

Unfortunately this is a software issue on the latest update for your Windows Phone. You'll just have to wait for a new update to fix this issue.

http://forums.windowscentral.com/nokia-l...

E.g:

Manufacturer Name: RM-985_1005

OS version: 10.0.10586.218

Firmware Revision Number: 02040.00021.15235.53003

Hardware Revision Number: 1.0.0.0

SOC: 8926

From what I can gather, I think when the operating system got updated to that version or newer, it updates the firmware for the rear camera which I think was bad firmware which has basically bricked the camera. The posted link has users saying that they have even tried rolling back the firmware which did not fix the rear camera issue. I think you will need to get your phone fixed / replaced under warranty if you still have it.

Note: Probably best to wait for another update to come out and fix this issue, it might be able to fix the rear camera.