Custom OS samsung galaxy e5 Is there any chance of installing official Samsung galaxy s5 6.0 marshmallow firmware on samsung galaxy e5 using odin?
It is possible to install official firmware on the samsung galaxy e5. However samsung hasn't released a marshmallow update for the e5 yet.

In the android ROM community they call official firmware, "stock".
When looking for posts online it is best to search for "flashing stock rom Firmware"

You can use Odin to install the official samsung galaxy e5 firmware. Be aware that there are multiple versions of the samsung galaxy e5 and you need to find the correct firmware for your device. Too view your device model go to -> settings -> About Phone -> device model.

There is however a unofficial cyanogenmod rom available for the samsung galaxy e5(E500H only) that has marshmallow.
Forum post to E500H Cyanogenmod