• Print

Junk E-mail (spam) Filtering

Overview

In order to reduce the amount of junk mail (spam) reaching your Inbox every day, Computing and Networking Services (CNS) has installed Anti-Spam Filtering software at the UTORmail postoffice. The software will redirect suspected spam from your Inbox to a folder named junk-mail, which will be automatically created for you. Messages older than seven days will be regularly deleted from your junk-mail folder.

You must regularly check your junk-mail folder for misclassified good messages and move them to your inbox.

Here's How It Works

By default, the anti-spam filter and accept list feature has been enabled for all UTORmail customers.

With the anti-spam filter turned ON, messages suspected of being spam are automatically delivered to your junk-mail folder instead of your Inbox. Some spam messages may still be delivered to your Inbox - anti-spam filtering is not perfect.

You can set anti-spam filtering to be very strict or less strict depending on your tolerance for good messages being filtered into your junk-mail folder. This is done by selecting one of four spam filter risk levels: Low, Moderate, High or filtering OFF.

• Low risk means fewer good messages may be detected as spam
• Moderate means a few more good messages may be detected as spam
• High risk means even more good messages may be detected as spam
• OFF means all spam will be received in your Inbox

By default, the filter has been set to Moderate.

Important: Whatever risk level you choose, you must regularly check your junk-mail folder for misclassified good messages that are captured by the filter and move these messages to your Inbox or other folder. Messages older than seven days will be regularly deleted from your junk-mail folder. We encourage you to delete messages from junk-mail once you have confirmed they are all spam.

To change your filtering level, here's what you do:

Note to Faculty and Staff: If you have someone in your department responsible for maintenance of your computer (installing software, fixing hardware and software problems, handling network connectivity, etc), please check with them before making changes.

1. Go to the UTORid account management site, login with your UTORid password and select the modify option
2. Choose Option 4: change the risk level of junk email filtering
3. Select the option appropriate for you.
4. Click the "submit the modification request" button.

The change will be in place the next day. You can alter your anti-spam settings at any time by returning to the UTORid account management site.

Accept lists

Each UTORmail customer can add email addresses to their accept list. Messages from senders on your personal accept list are always sent to your Inbox. Such messages will never be incorrectly identified as spam (also known as false positives).

In general, it is not necessary to add everyone who sends you messages to your accept list. False positives in such cases are rare. However, some newsletters have characteristics of SPAM, and the sender email address should be added to your accept list if you want to ensure delivery. (The technology used limits each person's accept list to 100 email addresses.)

The following describes how you can create and add email addresses to your accept list,

1. Login to UTORwebmail at https://webmail.utoronto.ca
2. If you have an email message from the address you would like to add to your acceptlist, in the message index, click the checkbox in the left column next to the message. Then click acceptlist below the UTORwebmail toolbar.

It is also possible to directly manage the accept list,

1. Click the Filters icon on the Webmail toolbar to go to a list of already existing rules. 

2. In the "Existing Rules" column, click the word acceptlist. 

3. An Accept List page will appear, where email addresses can be added or removed, one per line. 

4. When done editing the list, click the Save button at the bottom of the panel.
5. After saving, click the Return to Rules List button at the bottom of the panel. Verify there is a green checkmark in the "Enabled" column next to the accept list rule. If not, click the red X to enable it.

Your changes should take effect within the hour.

Note that even though customers must use UTORwebmail to manage accept lists, the list applies to your messages no matter how you later access UTORmail e.g. UTORwebmail, Thunderbird, Outlook, Outlook Express, etc.

Frequently Asked Questions

What is spam and where does it come from?
See the original Spam FAQ - the time before filtering.

I can't find my junk-mail folder!
The junk-mail folder should appear and require no additional intervention. Should that not be the case, you may need to subscribe to junk-mail in order to see it. Please consult with an advisor at the Information Commons Help Desk for assistance in subscribing to the junk-mail folder. Call 416-978-HELP.

Will my other email addresses also be filtered?
The anti-spam filter function only works on email handled by UTORmail. At present, only email arriving to addresses ending in @utoronto.ca can be filtered. Some departments run their own email systems independent of UTORmail. Messages going directly to such systems are not affected by this filter.

If I forward mail from my UTORmail address to another address, will my email be filtered?
If you forward email addressed to any non-UTORmail account, the spam will not be filtered. The anti-spam filtering only works if you are reading your email directly from the UTORmail postoffice.

What happens to anti-spam filtering when I go on vacation and set my auto-reply?
When the anti-spam filter and the auto-reply function are on at the same time, anti-spam filtering will happen first. This means the vacation message will only be sent in response to messages that get past the anti-spam filter. This is good since responding to spam often just produces more spam and delivery failure notifications.

If you will be away for more than seven days (remember messages older than seven days will be regularly deleted from your junk-mail folder), you may want to turn the anti-spam filter off or reduce your risk tolerance setting to Low Risk. This will reduce the risk that good messages which filter to your junk-mail folder will be deleted in the seven day cycle.

Will email be delayed as a result of the filtering?
There will be a moderate delay.

What happens if I accidentally delete my junk-mail folder?
Beginning in July 2005, the first time there is a message to be delivered to the junk-mail folder, it will be recreated.

What if I really want spam in my INBOX?
Turn the anti-spam filtering off (instructions here).

Are viruses are being scanned for?
Yes. Computing and Networking Services (CNS) has installed an anti-virus filter at the UTORmail post office. For more information, please see UTORmail Virus Filtering.

However, it is important that everyone use anti-virus software on their desktop computer. Symantec Norton Anti-Virus (NAV) software is freely available to all faculty, staff and all students enrolled in degree-granting programs of the University for both on- and off-campus computers. To learn more about the anti-virus service, please visit www.antivirus.utoronto.ca.

I am technical staff, technically advanced or just curious about how the anti-spam filter works - where can I find more information?
Please visit our advanced explanation page.

Not a good idea for POP email programs
Most people use email programs that read messages directly from the central email servers using a technique called IMAP. Some people use a method called POP which usually downloads your entire Inbox to your local computer when you first connect to the email server. POP has never been supported or recommended for UTORmail.

While the anti-spam filter may seem to work when you use a POP email program, it is not recommended because such email programs often do not give you a simple way to check your junk-mail folder for any good messages you might want to save.

If you continue to use a POP email program and the anti-spam filter, the suggested compromise is to use the Low Risk setting via the UTORid management page. Low Risk will minimize the chances that good messages will get into your junk-mail folder.

Acknowledgements

We wish to thank the University of Washington and the University of Ohio for sharing their anti-spam documentation. We also appreciate the technical expertise that the Unversity of Washington shared with us.

Revisions

Modified January 29, 2008 for new acceptlist feature