leaving game once you are destroyed

Hunter1911: Try doing an integrity check. It will check if your game has any corruptions. Please create new shortcut for wot launcher.
Add -integrity in target as "D:\Games\World_Of_Tanks\WOTLauncher.exe" -integrity
  To explain what a mod is: it is a modification of the game. But as you have stated not to use them, no need to worry about that.