When I went to install WWT, the setup program launched the DirectX 9.0c. Since Vista is DX10 based, I canceled the installation for DX and completed the program installation.
Do I need to let the DX9 setup complete, and will this mess up the DX10 settings in Vista?
As I understand things, there's actually two versions of DirectX on Vista: 9 and 10. Apps that use DX9 may still need that version to be updated even though there is DX10 sitting around as well (they're not compatible with each other, unlike earlier DX versions).
So, I believe you may need to let the DX9 setup complete, and it won't mess anything up.
TeutonJon78: Do I need to let the DX9 setup complete, and will this mess up the DX10 settings in Vista?
Yes, DirectX 9.0c is required. You can find the requirements on the download page on http://www.worldwidetelescope.org
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