It appears that not all Windows 7 pre-installs come with driver support for DirectX-10 compatible with DCU Online. Attempts to run the game from a fresh install on a new system can report errors of missing dlls (e.g. Xinput1_3.dll missing).
It is highly advised that you don't try and download/install the missing components from one of the many "DLL Download Sites". Instead, please refer to Station support at
DirectX 10 WARNING: Due to a lack of updated drivers to support it, we currently cannot guarantee support for DirectX 10 for any of our supported cards. If you have already upgraded to DirectX 10, we recommend that you install 9.0c (August version) at the earliest opportunity. 9.0c will not over write DirectX 10 but installs alongside it and provides files that are missing from the DirectX 10 installation.
Or obtain the official microsoft distrobution available at