You should temporarily turn off your antivirus software when you are installing new software. Especially printer software. If you don’t, you may end up with a corrupt installation. Sometime it won’t tell you it’s a bad installation, it just won’t work correctly.
Be sure to turn the antivirus software back on when the installation is complete.
And ALWAYS set a password on your antivirus software, something a bit more secure than “password” or the like. Many types of malware are counting on an easy—or no—password so that they can turn off your antivirus program to escape detection.