The solution for this issue has been recently posted in the Autodesk Knowledge Base. ID TS1106848 2009-Apr-14

After installation, you were able to start the product, but when you tried to execute a command or select one of the UI items, the product crashed with the following error message:

Unhandled e0434f4dh exception at 7c81eb33h

This error is caused by Microsoft .NET Framework 3.5 Service Pack 1 not being installed properly.  You can download and install Microsoft .NET Framework 3.5 SP1 directly from the Microsoft website here

Once you have installed .NET Framework 3.5 SP1, the product will work as expected.