I already posted a lot about the problem in a previous thread on this forum.

There simply isn't much more detail I can give about the problem for one simple reason:

I launch it, and it crashes instantly, in less than one second - not even completing showing the start up splash screen.    That means there's not a lot to work with in terms of making adjustments.   While I sympathize with needing reproducability to fix errors, this constitutes a pretty major flaw for which they offered no helpful suggestions.  

My version of Windows 7 is vanilla-generic, right out of the box.  I have not made customizations to the operating system in any way that should need any adjusting.
My personal suspicion is that the issue is one of compatibility with my video card, but they offered no insight on that either, and I'm afraid that would be a coding issue, not a settings issue.
Previous versions of Carrara worked fine on the same machine, and even the 32 bit version works fine on this machine.  I'm not running anything concurrently with Carrara that should have even a remote chance of interfering with its operation.

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