Here is a proven way for those of you that struggle to connect your Ti89 calculator to a MAC computer. This is what you need to do to get connected: Uninstall TI Connect v4.0 if installed. Download and Install TI Connect version 4.1  : https://education.ti.com/ticonnect/ticonnectmac41 . Beware: this link immediately downloads the .dmg file to your… (read more)