is email scan really necessary?

One antivirus software usually consist of realtime scan or defend,email scan,and etc. I just want to know that is email scan really necessary? Because if there is a virus in that email,i mean just in the accessories…when it is unpressed, the realtime scaner or defender will find and do with it? is it?

 

You are correct that email scanning is unnecessary, especially outgoing email scanning since the message has already been scanned when you save it prior to sending. However AV programs such as Symantec Norton AV and Grisoft AVG support it and some prefer to enable it anyway.

 

Depends on settings od the particular scanners. While the realtime scanner may not unpack the content of specific archives (e.g. ZIP) for performance (or other) reasons, the e-mail scanner may process them. So, if this is the case, the realtime scanner wouldn't detect an infected ZIP file [= a ZIP archive containing an infected file inside] being attached, while the e-mail scanner would.

And, as usually, there's always the possibility of an e-mail client exploit - with the malicious code being in the e-mail body itself, not in an attachment.