wheeler,
Please follow these directions:
1. Open Windows Explorer
2. On the menu bar, choose Tools»Folder Options.
3. Select the File Types tab.
4. Choose the VI extention in the box.
5. Press the Advanced button.
6. Select the open action and press the Edit button.
7. Make sure LabVIEW 6.1 is the application in "Application used to perform this action." For you, this should just involve changing the "LabVIEW 6" section of the directory structure to "LabVIEW 6.1".
I would also keep the RegisterExtentions=False line in the LabVIEW 6i INI file.
Randy Hoskin
Applications Engineer
National Instruments
http://www.ni.com/ask