E-mail scanning

I posted a while back about a long delay when starting Outlook 2010 (on Windows XP).  When NIS 2014 was configured to scan e-mails, it would take from 2-10 minutes before Outlook would start receiving emails from the server.  I was able to "fix" this by turning off the "Anti-SPAM" scanning of emails.  This led me to think about a few questions...

1. What is the difference between email "Anti-Virus" scan and email "Anti-SPAM" scans?  I can guess that the SPAM does not have "dangerous" content--just junk mail whereas the Anti-virus may contain harmful content?

2. I only occasionally see an email placed in the Outlook Anti-SPAM folder.  Most of the real spam is being caught by my email provider (before NIS even sees it).  I don't think I have ever seen an email flagged with a "virus".  How does NIS identify these Anti-Virus emails?

3. Since I don't believe that I have ever seen an email flagged with a virus, does that mean that none were found?  Or does NIS delete them without notification?

4. I wish I knew what NIS was doing in the 2-10 minutes of disk activity before Outlook starts receiving emails from the server...  All I know is that if I turn off Anti-SPAM scanning the delay goes away and Outlook starts receiving almost immediately after launching.

5. Would I be making a mistake to assume that since I hardly ever see a "NIS-flagged" SPAM e-mail that it would be relatively safe to disable the Anti-SPAM email scanning?

Any comments or ideas?

Thanks,

Mike

How can you make Norton not scan them? I ended Norton 360 and still does it...

I have a LOT of spam mail with viruses in and I want see what idiots have sent me.