Why is my camera on mobile not working

[AC Question]

I have samsung galaxy j5 with officialy android lollipop and i updated on marshmallow and my camera stopped working. If i run camera is black screen

 

[AlphaTango414]

Sounds like a software issue if it happened right after an update. First try booting into recovery and wiping system cache partition. This does not wipe any personal data from the device.

Only next step is can think of, if the above did not work, is doing a full factory data reset via recovery mode. THIS WILL DELETE ALL SAVED DATA PERSONAL AND SYSTEM.
A data reset is sometimes needed, normally suggested, when doing a major update such as 5.1.1 to 6.0.1