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thanks for that, now it asks me the key and opens the other window but it stays in "Logging in..." and nothing happens

Always post your log file after a new attempt, its very important for people to help you.
Make sure your world of warcraft is set to run the 32 bit client and that you're also set it for DirectX 9 and windowed mode, see below image:
WoW 32 bit client (NOT 64 BIT CLIENT)
WoW in Windowed mode (Menu --> Options --> Graphics --> Display Mode: Windowed (NOT FULLSCREEN))
WoW in DX9 mode (Menu --> Options --> Advanced --> Graphics API: DirectX 9 - requires client restart)
WoW & HB must be ran as Administrator