The Good, The Bad, & The Unknown
Legacy AntiVirus products allow Unknown applications to execute on your computer!
A computer file could be an executable or non executable type in general. The executable one is full of instructions telling the CPU (the intel thingy) what to do, like show this character on the screen etc..just full of instructions..sometimes, these instructions could be some malicious things like, copy the password and email it to fraudster etc… Unknown.
So if you don’t want to run your computer or your business like a lottery and letting your security applications run “unknown” applications, then better use Comodo.