I too have been getting those "microsoft latest security patch" and
"couldn't be delivered" emails. I don't open the attachments either but they
all have .exe on them and I run a Mac, so they wouldn't work on my computer
anyway. I've been getting 20 or so of these emails every day for about two
weeks now! I finally created a "rule" to delete these little puppies as soon
as the arrive because I got so tired of my inbox being flooded with them.
Very annoying!

I'm assuming since I run a Mac I don't have to worry with this or am I
wrong? All the virus scan stuff that is for "free" or what have you are
always for Windows based systems. The guys at the Mac store told me I really
didn't have to worry about it because almost all viruses, worms, etc. are
windows based. They told me to never download and run program installers
from the internet unless I get it from Tucows, CNet or some other reputable
internet based software place and I know I haven't run any type of program
that was downloaded unless it was from one of these.