The protection against unknown threats protects your computer from unknown viruses and blocks potentially dangerous attachments, as well as scripts that could represent a risk.
Follow these steps to enable or disable the protection against unknown threats:
Click Antivirus in the main window of the program.
On the left-hand side of the window, make sure the Unknown viruses option is selected.
To enable the protection against unknown threats, set the control to the ON position. To disable it, set it to OFF.