Information on Spam and Defence against Email Viruses

The main points for protecting our users from spam and email viruses can be summarised as follows

• an intelligent greylisting method is used for incoming emails
• all incoming emails are checked for spam and viruses in real time
• every email containing non-readable attachments (e.g. password-protected documents) is rejected
• every email (both incoming and outgoing as well as within the university) is checked for spam and viruses
• there is a limit on the rate of emails that can be sent (200 emails per user per 24 hours)
• there is a limit of 300 email recipients per hour
• verification as to whether the sender address belongs to the account of the sending user

Incoming emails are checked in real time for spam and viruses. If an email is not declared as "clean", it will not be accepted and the sender is immediately informed as to why the email could not be delivered.

The following file types belong to the unauthorised attachments: Overview of blocked file types [de].

The advantage of this procedure is that there is no need for tagging or for setting up so-called quarantine zones.

Just because an email is sent within the university network doesn't mean it can't be spam or contain viruses. That's why every sent email is checked.

Users are able to send 200 emails per day. This measure is necessary to prevent abuse of our email system, e.g. through compromised user accounts. As soon as you want to send more emails, the central mail server will refuse to accept your email and notify you with the message "Rate limit exceeded". This restriction is automatically revoked after 24 hours.

As the reliability of the central spam and virus defence is very high, we strongly recommend you switch off local spam filters.

Even if you think that you receive too many spam emails without local spam filters: every user has a different perception of what spam is. No individualised local filter will help here either, as this can lead to false recognitions.

In addition to actual spam emails, there are also phishing emails, which are intended to steal users' access data. Phishing is not SPAM! Phishing emails are targeted attacks on users and not worldwide mass mailings. Therefore, spam protection methods generally do not work here. The University Computer Centre endeavours to set individual filters as soon as it receives notifications of phishing.

We urge you not to respond to such emails.