You want to have an antivirus to be installed before plugging an external device, not after. It is very important to have this step done first.

Download And Install Antimalware App For Mac Here’s How To Scan External Drives For Virus On Mac 1. Now, let’s unpack what I suggested above. Do not open any documents or run any programs on the external devices until the virus scan is completed. Do not use Malwarebytes as it does not have the capability to scan individual disks. There are free antimalware apps, such as Bitdefender or Avast, that can scan a USB drive for viruses on Mac. He was afraid that he could catch malware on his MacBook by simply inserting a disk. Naturally a very cautious person, my friend first called me and asked whether it’s safe just to plug the flash drive in or is there a better and secure way. His coworker gave him a USB flash drive with a program that needs to be installed on his laptop. My friend, who knows that I run a blog about Macs and especially the security aspect of Apple computers, called me yesterday and told me about the situation in which most Mac users would be one day.