Try using the DirectX Diagnostic Tool to help pinpoint the problem you are having with DirectX. To do so, click the Start button, type dxdiag in the search box, and then press Enter.
This troubleshooting information may help as well - http://windows.microsoft.com/en-us/windows7/Diagnosing-basic-problems-with-DirectX
Hope this helps and let us know what happens.
Microsoft Windows Outreach