A while ago I had a problem client.exe closing immediately after starting it up.
The problem was reported in one of the log files as D3DXAssembleShader returning -2147024770
HRESULT 0x8007007E is "The specified module could not be found."
So I installed The Microsoft DirectX® End-User Runtime.
Now it works fine.
Seems like the installer should take care of this dependency though.
Also client.exe probably should report something to the user.
Currently using Windows 8 Pro btw