After installing one AT-MIO-16XE-10, two devices show up in Windows Device Manager. The OS is Win2000. I don't know if this is normal or this indicates a problem.
Try searching through ni.com/support to see if any KnowledgeBases or other members of the community have had this issue. I searched for "AT-MIO-16E-10 Device Manager" and found this:
KnowledgeBase 3DEH4PNQ: Why Does My AT/ISA DAQ Board Show Up As Two Devices Under Device Manager?