Yes, server protection is only one part of an effective solution
to fight viruses. Infection can also occur when downloading
programs, browsing webpages, using floppy disks, etc. This is
why good virus scanning software on the workstation is still a
necessary part of the total solution.
Yes, you still need to be leary of opening attachments that
you were not expecting. You should also still run virus checking
on your computer regularly.
No, currently we block email containing viruses from delivery
and generate a bounce message to the sender stating what kind of
delivery problems there where and what they need to do to
correct them.