Now I'm sure. This is the third time it happens to me.
I proudly find an Universal Flashlight, my goal is to attach it to my favourite weapon : the M4A1. So I attach a 9V battery to the Universal Flashlight, then I attach this one to my rifle.
It's OK, it perfectly works… until it's time to diner (what a mess).
So I log out and close the DayZ client.
A few minutes later, when I log back in the game, the night has Fallen. What is my first reaction ? Turn my rifle flashlight on. So I left click on my mouse and… Nothing happens. Hum...
Maybe the battery is dead ? Let's see that.
W... wait… WHAT !? My Universal Flashlight isn't attached to my favourite rifle anymore !
Then I lost one 9V battery and one Universal Flashlight. :(
I'll never log out for finer anymore !