Updating S7 Edge using Odin: stuck in Download Mode's "Downloading..." I have done the following steps (in this order) to update my Samsung Galaxy S7 Edge using Odin:
- Downloaded and installed the Samsung USB driver on my Windows PC
- Enabled USB Debugging on my phone
- Booted my phone into Download Mode
- Opened Odin (v3.12) on my PC
- Connected my phone to my PC (confirmed connected by Odin)
- In Odin, selected the BL, AP, CP and CSC (intentionally instead of the HOME_CSC, as I wanted a reset as well)
- Clicked Start

It has now been 1.5 hours, and the phone's Download Mode screen is still showing "Downloading...".

Did I do something wrong? It's not meant to take this long, is it? (I read that it's meant to take no more than 20-30 minutes)

EDIT: after over 2 hours with no change, I force reboot my phone, after which I was greeted with the following error:


  "Device storage corrupt. the data partition has been corrupted. you
  need to reset your device to factory default settings. this will erase
  all your data"


I am now downloading the latest UK Oreo ROM, which just came out yesterday, in hopes I can manage to flash it successfully and that I haven't bricked my phone beyond repair...
Okay so I eventually managed to both unbrick my phone and install Oreo. Here is how I did it.

Unbricking the phone:


When the phone is off, press Power + Home + Volume Up (yes, up)
Don't worry about the weird messages, just wait a minute
A menu will appear with several options, one of which will be to factory reset the phone. Use the volume keys to go to this option, and then the power key to select it
As if by magic, your phone will reset and then be unbricked, and the OS will load normally


Installing Oreo - what I missed was:


Enabling OEM Unlock in Developer Options in the phone's settings
Using the latest version of Odin - v3.13.1 - it appears that anything older won't work
(possibly) Running Odin as administrator on the PC


I recommend this video tutorial to install Oreo: https://www.youtube.com/watch?v=mdSIyk7lkd8

Good luck!