Why can't my calculator connect to my MacBook Pro?

I use a TI-84 Plus (recently upgraded to version 2.55) and a TI-89 Titanium on a regular basis for school, and I create my own programs for my benefit. I have connected both calculators to my PC with TI Connect multiple times without a problem to sync programs and rearrange files, but I want to use TI Connect X for Mac to use the new version with a program editor. Upon installing TI-Connect and connecting my calculator(s) to the computer, I receive no indication that my calculator is seen by the application. Only after turning off and then back on my calculator do I get this message:

It reads: "Alert - A device was connected, but we could not communicate with it for some reason."

This has happened with both my calculators every time I try. I have uninstalled and reinstalled, used different cables, downloaded the software again, and connected to different usb ports, all to no avail. I sought out help from TI for this, and it was concluded that the problem was probably with my MacBook Pro because I am still able to connect to my PC and my friends' Macs, under the same conditions.

Does anyone know of a reason for why my TI-84 Plus and/or TI-89 Titanium cannot connect to my new MacBook Pro using the TI Connect X software?