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What is the VPOP3 Antivirus solution?

“VPOP3 Antivirus” is a new product to replace the avast! for VPOP3 product which will no longer be supported after the end of 2012.

VPOP3 Antivirus uses the popular 'ClamAV' virus scanner to scan incoming and outgoing messages for viruses.

What is ClamAV

ClamAV is a popular open-source antivirus program. While it is not as effective at detecting viruses as avast, it still detects most viruses.

It is commonly used on ISP mail servers for checking for viruses as messages pass through.

Why ClamAV

We have tried to continue using the avast virus scanning engine or find an alternative commercial low-cost virus scanning engine which we could integrate into VPOP3, but have not been able to do so yet - we will continue looking. (If anyone knows of one which we could licence, we would be glad to investigate further).

Because most people want a low cost antivirus solution on their email server, we decided to develop a low cost ClamAV integration rather than produce another, more expensive, option.

Isn't ClamAV free?

Yes, ClamAV is published under the GPL v2 licence, so the source code is downloadable free of charge.

However, it is not easy to use the ClamAV software with a program like VPOP3. The VPOP3 Antivirus product which you purchase from us includes the software to easily use ClamAV from within VPOP3 and also support for this integration.

We have modified the ClamAV software slightly for use with our plugin (primarily to try to stop infected emails triggering other antivirus programs installed on the VPOP3 computer). The source code containing these modifications is available from us on request.

ClamAV is provided under the GPL, doesn't this mean VPOP3 has to be GPLed now?

No, VPOP3 does not link into the ClamAV libraries at all. The VPOP3 Antivirus plugin executes the 'ClamAV daemon' as a separate program, then communicates with it using a documented TCP/IP protocol. This means that they are treated as separate programs.

GPL FAQ

Options

If you have used avast! for VPOP3 in the past, what are your options now?

There are several options available to you:

  1. don't use a virus scanner on the email server at all. As long as you have a virus scanner on each user's PC, then that should protect against infected emails as well. Having a virus scanner on the email server is a good idea, as it is a second line of defense, but it is not vital as long as your PCs are already protected
  2. use the VPOP3 Antivirus (based on ClamAV) product. This is a simple low cost option which integrates with VPOP3. This requires VPOP3 version 4 or later
  3. use Sophos SAV Interface. This integrates with VPOP3 and works with VPOP3 v1.5 or later.
  4. use MailScan for VPOP3. This works with any version of VPOP3

NB - we can only supply Sophos SAV Interface within the UK. If you are outside of the UK, you should be able to find a local supplier.

You can contact us by email or telephone (01484 855800) if you have any questions about what you should do.