An error occurred downloading game data

I can’t launch HoTS on my PC, with error log summary as follows: e_errorIdStreaming (NGDP:E_NOT_AVAILABLE) “An error occurred downloading game data from Blizzard’s servers. Please check your internet connection and try again later.” Report ID: 00000000-0000-0000-0000-000000000000

The connection works fine and I’ve already re-installed the game. Does anyone know what is causing this issue?