Opening files on our computer is problematic. Then, we do not know what is in the code. So, disable previews for email protection antivirus.
First, there is a healthy fear of what we do not know with good reason. Unknown attachments are not to be opened. Given, good netiquette.
First, we do not look in program file folders often. Next, malicious code can hide there, So, scan all directories for malware with antivirus to be safe.
Now, we use different programs for web surfing than program installation. Hence, software protection for online activities is antivirus.
First, we must look around before we choose. So, software research to get a good antivirus program. Then, good netiquette.