Understanding how Anivirus works
Here's 2 scenarios I encountered:
Installed an Antivirus on a PC;
One month later (scheduled), I scanned, found a good number of detections/infections, then cleaned them.
My questions are:
a- Shouldn't the installed Antivirus prevent viruses from getting onto the PC? or an Antivirus function is just to detect them after scanning?
b- If the Antivirus function is to prevent, should I drop that Antivirus?
There is only one Antivirus that I know that scans fully removable devices (flash memory, external HD) before giving the possibility to open them; others try to detect, clean but give the possibility to open them which put the PC at risk; therefore, I ask people not to open the removable device, go to My Computer, right click on the removable device and scan it before opening it (which most peole forget to do)
My question is:
a- Will I go for such an antivirus that fully scan the removable device before giving the possibility to open them?
Thank you a lot,