antivirus filter for email

It’s good to have more than one proposal,
during presentations there are more possibilities
to receive a expression of interest.
Until now the winner is doublebackup.

Last Thursday I talked with a partner of Realsender.
I showed him doublebackup and Spamstop.
He was more interested in doublebackup.

He made some encouraging comments on SpamStop:
“It’s a sort of whitelist,
does it have any antivirus filter? (no)
In this case it’s not good to protect enterprises
we are looking for a full protection solution.
There are services that provide a sandbox
where the user can safely open links and attachments.”

The framework behind SpamStop was originally written
to filter attachments. So I started tinkering with it.
At first it filtered by file extension only,
after testing for a whole day it filtered all attachments,
except the specified extensions (.pdf and .txt).
That was exactly the behaviour that I was looking for!

Googling for a technical solution, I’ve found a case study,
that ended with a promising sentence:
“For us, attachment filtering has been very successful”
web.mit.edu/net-security/Camp/2004/presentations/reillyb-mit2004.ppt
I’m confident that this feature will be highly appreciated.