Check for malware on outgoing mail

[t-mug]

How could I prohibt relaying of outgoing mails which contain malware? The standard behaviour of ispconfig mail configuration seems to be not checking this.

In which file have I to change what settings? I would like 1.) to send an email back to my mail sending customer with a warning about the interrupted mail transfer and deleted mail - and of course: delete the mail - and 2.) to deny incoming malware mails after virus checking and sending back a deny message to the sending server logs, which seems also not to be the standard configuration of ispconfig.

Can you give me a hint?

[till]

ISPConfig scans the email when they are received with procmail.

The behaviour that you want can not be implemented with procmail, so you might have to install e.g. amavisd into your system to check the outgoing emails.