Can't run games, missing a DirectX DLL File?

Can't run games like MS Flight Simulator X or Medieval 2... get error D3DX9_30.dll is missing, and invalid version of Directx. I ran autoupdate on MS site, directX is current (9.0c). DXdiag shows no problems. When I try to reinstall get an 'internal error' and installation fails. Tried several releases inclucluding December and April. Running MS PRofessional X64.


Here's snipplet from dxerror.log:





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[01/09/07 15:08:36] module: dxupdate(Mar 31 2006), file: dxupdate.cpp, line: 2221, function: RegisterDLL





Failed API:LoadLibraryEx()


Error:(193) - %1 is not a valid Win32 application.











Unable to load C:\WINDOWS\system32\xactengine2_1.dll.





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[01/09/07 15:08:36] module: dxupdate(Mar 31 2006), file: dxupdate.cpp, line: 5763, function: DirectXUpdateInstallPlugIn





RegisterDllFromSection() failed.





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[01/09/07 15:08:36] module: dsetup32(Mar 31 2006), file: dxupdate.cpp, line: 280, function:

Can't run games, missing a DirectX DLL File?
Re-download and install DirectX from http://www.microsoft.com/downloads/detai...
Reply:That's Right : youn can't run the program "Flight Simulater or


Xmedieval2 unless yourself has gp-force mix 4000 /Vedio Graphics Card installed plus buy the3D Force Joystick as required !


see http://www.flightsimulator.microsoftware...


then refer http://www.xmedieval2.repairs .Those are for windows


xp 95-98 updated types ok ?
Reply:Don't feel left out, because I just searched my system and D3DX9_30.dll could not be found, either.


http://www.gamedev.net/community/forums/...


See a discussion of the problem here. And while yo are at it type


D3DX9_30.dll in the search line of your browser. There are a bunch of fixes from renaming to downloading a .dll.
Reply:Insert your WinXp Cd %26amp; go for the repair option in the installation process. That should solve it!