I don't have a specific answer, but I wouldn't be suprised if there is.
For example, we use Solid Edge and keep a copy of AutoCAD 14 on our computers for legacy data. When we get to update our computers, we have to load SE first and then AutoCAD because of dll conflicts.
No one knows exactly why, including Solid Edge support. But, they've seen enough cases of where the strange sporads dissappear when installing the software in this order.