I've had this twice now so this is not a one time event. It's also not happening for any other game other than ESO. No other installed game disappears without trace or any warning.
Steps:
- Update present in my games and apps along with other updates. Use cancel all to cancel multiple updates
- Try to update ESO only but find that ESO is no longer installed within games
Clearly there is something to be said for not cancelling updates but this is without doubt a bug for ESO and not XBOX. There are no reasonable circumstances under which cancelling an update should remove the entire game.
There is no warning that cancelling the update will remove the game like you would get if you went into manage the game. The game is just gone.
This happened on my primary console and I was faced with a 60+GB download. I went to an old console that at least had the pre-Summerset version of the game and tried to network transfer that install across to the console that had lost the game. This didn't work as it wanted to update. Needless to say, cancelling the update on old console lead to the entire installation disappearing again.
No other game that wants to update e.g. Minecraft, Warframe, The Division disappeared when I cancelled updates for them
There is something seriously wrong with the installation/update mechanics for ESO