After the installation clamav activates itself automatically, which can be verified under status -> Services.
ClamAV is now installed, so activate the “squidclamav” in the proxy settings. If “squidclamav” does not show up here, verifiy that you installed BOTH packages.
Important: ClamAV requires more Squid proxy filter processes (when enabled it increases the number of Squid proxy processes by 10). This in turn leads to a more memory being used. If your IPFire box has a small amount of memory (< 512MB) you should seek advice in IPFire chat.
To test the security of your ClamAV installation, download the standard Anti-Malware test file from the EICAR organisation using HTTP (not HTTPS!). This is not an actual virus and should do no damage to your system.
If you see problems with streaming media, like Youtube, check these instructions.
You can manually update your virus signatures with the following command over the Console: