Can you run me through what happens before you attempt to Salvage from the Gear vault?
Also, have you only experienced this in the Gear vault and not the Minion or Spell Vault?
And when you return from force closing, are you able to return to the Gear Vault and Salvage as normal? Or return to the game as normal, as you mention being unable to play the game now?
As we are aware there is an issue when attempting to salvage all weapons including last weapon get the message ’ Unable to salvage last weapon’ and then the UI has some issues… but this does not sound like the same as what you have described