2.  Step1: Replace the cable and check if the error is not resolved move to next step.  Step2: Connect to Mac using USB cable to android phone.  Step3: By pulling down the top screen open settings in the android phone.  Step4: In settings open developer options and select USB debugging mode on and try to reconnect the android to the Mac.

3.  Step1: Make sure that your Mac is installed with Mac OS X or latest version than that as earlier versions are unable to support the connectivity between Mac and android device.  Step2: Restart your Mac computer.  Step3: Open file transfer application on your Mac.  Step4: Now connect android device to Mac computer.

4.  Step1: Check for latest update of android software and install updates.  Step2: Now reboot android device and check whether getting connected to Mac.