Updates, Service Packs and Extensions for 3ds Max and 3ds Max Design need to match the version they are installed on.
Therefore, you will need to install the connection extension on the appropriate version of 3ds Max/3ds Max Design. For example:-
3ds Max Design 2010 English 32-Bit - You will need to install the English 32-Bit version of the Connection extension for 3ds Max Design 2010
3ds Max 2010 Englsih 64-Bit - You will need to install the English 64-Bit version of the Connection extension for 3ds Max.
Regards,
Vivek Ramesh
Autodesk Product Support
Vivek Ramesh
Product Support Specialist
Global Services
Autodesk, Inc.