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WiscMail / WiscMail Plus - Filters, Anti-Spam and Anti-Virus FAQs

About the Filters, Anti-Spam and Anti-Virus service.

WiscMail messages are rated on the likelihood that each message is spam. Users who opt-in to this service are able to select a score for messages that they would like to have delivered to their "Junk Mail" folder in their IMAP/Web Mail account. The WiscMail administrators have set a 15 day expiration timer for messages that are in each user's Junk Mail folder so that spam will automatically be deleted.

Since one person's "spam" is another person's "ham", there is a likely possibility that the anti-spam scanner will falsely identify some types of e-mail messages. A false-positive is a legitimate message that was identified as spam. A false-negative is a spam message that was identified as a legitimate message. DoIT will minimize the likelihood that messages get falsely labeled as false-positives or false-negatives. Nevertheless, DoIT provides ways to over-ride the spam scanner's judgment if it is incorrect for certain messages.

WiscMail provides a server-side filtering service for use with accounts enabled for IMAP or Web Mail access. Users can choose to filter their spam into their Junk Mail folder. Users can create a "Block List" of email addresses that should always be filtered into your Junk Mail folder. Users can also create a "Accept List" and a list of subscribed Mailing Lists so that messages from (or to) these addresses will never be filtered by the Junk Mail Filter or the Block List. Finally, custom filtering options are provided so that users can sort their mail in a custom fashion.

How to set up your filters

Server-side filters
Client-side filters

All messages are scanned for viruses. Virus messages are discarded and not delivered if they and known to be of the self-propagating type. All other viruses rated with the highest spam score and then delivered. For more information about the anti-virus policy, view WiscMail / WiscMail Plus - Email Virus Protection

How do I view my Junk Mail folder?

If you POP your email, you must use the WiscMail | WiscMail Plus web client to check your 'Junk Mail' folder.

If your email client is configured to use IMAP, view the contents of your 'Junk Mail' folder. If you do not see your 'Junk Mail' folder, you may need to subscribe to your Junk Mail folder.

Are UW addresses automatically exempted by the spam scanner?

Yes. Any messages sent from the web client or a desktop client using are trusted as not spam.

Do not put the '' in your Accept List filter because a lot of spam is forged with those addresses.

How do I prevent my messages from being filtered into Junk Mail folders?

  • Use, the web client, or DoIT's mass email service to send the messages (subject to UW appropriate use policies).
  • Consider sending the email as plain text, rather than as HTML which is often associated with spammers.
  • Ask the recipient to add your address to their Accept list filter. See document 2368.

How can I prevent getting spam?

The only way to not get spam is to make sure that spammers do not know your e-mail address or make them think that your account is not being read. There are many ways that you can try to limit the amount of spam you receive.

  1. Don't read or preview messages that you know are spam. Some spammers can detect whether or not you have read the message. Throw it away without reading it.
  2. Unsubscribe from the mailing list if the organization is reputable (you should be able to tell from their web site if they have one). Have you ever filled out one of those web forms and forget to check whether the "Send me Info" box was checked or unchecked? It's usually set on by default.
  3. Don't reply to spam messages and don't click the link that says "unsubscribe" if company is not reputable. Spammers often use this to verify that your address is valid. They rarely remove your address from their mailing list; or if they do, then they may just put you on another list.
  4. Obtain a "throwaway" e-mail address. Use this address if you have to enter your email address in an form online. Check the account periodically to make sure that no legitimate messages get sent to that address. Options include WiscMail Plus, Yahoo, Hotmail, etc.
  5. Read web site privacy policies before submitting personal information. This will help you determine if the company is reputable enough to handle your private information. If you determine that the company may abuse this information, give them your "throwaway" address instead.
  6. Don't put your email address on a web page. Spammers use "spider" programs to scour the internet looking for email addresses. If you absolutely have to publish your real email address on a web page there are some ways to hide your address so that people can read it, but spider programs can't. Look up these tactics with your favorite search engine.

How can I avoid missing email messages?

  • Check your Junk Mail folder on a regular basis.
  • Add senders or domains to your Accept List filter if certain messages are always filtering into your Junk Mail folder.
  • Add the addresses of your mailing lists to your Mailing Lists filter to avoid missing important messages from the list. Review manage filters document.

Will turning this feature on scan my Inbox for all existing spam messages?

No. Only new incoming messages. It will not filter existing messages or external-pop messages.

Are there any limits for the amounts of filters or block/accept/mailing list items I can have in place?

There is no limit.

Is there a way of configuring the filters from Web Mail?

There is a link to the configuration page in the option screen of Web Mail.

How does the web client "flag" messages with the spam score?

Look at the headers of the messages. You will see an additional header: X-Spam-Score. This header will contain only asterisks; the number of asterisks is associated with the Junk Mail filter level users configure.

What should I know about the 'Junk Mail' service if I am using Web Mail?

Mail obtained through the external POP feature is not scanned and will not be filtered.

The 'Junk Mail' folder is also accessible via the "Junk Mail" tab at the top of the message window assuming that the folder exists.

What should I know about the 'Junk Mail' service if I am using IMAP?

If you use IMAP to access your email account, you should have no problems using the 'Junk Mail' service.

Most IMAP email clients will not automatically see the newly created 'Junk Mail' folder. If you can see your 'Junk Mail' folder in Web Mail, then go to the following page, document 2377, to configure your client.

Most IMAP email clients will not automatically tell you if there are new messages in your 'Junk Mail' folder. We highly recommend that you periodically check the contents of your 'Junk Mail' folder.

Advanced users can choose to use client side filters instead of the server side filters. IMPORTANT: if you do decide to use client-side filters, make sure that your server side filters are configured not to collide with these.

What should I know about the 'Junk Mail' service if I am using POP?

If you use POP to access your email account, it is not recommended that you use any of the provided filtering options unless you periodically check your 'Junk Mail' folder via WiscMail | WiscMail Plus web client.

If you wish to use the filter options provided then it is suggested that you reconfigure your client to use IMAP.

Advanced users can choose to use client side filters instead of the server side filters. IMPORTANT: if you do decide to use client-side filters, make sure that your server side filters are configured not to collide with these.

What should I know about the 'Junk Mail' service if I have a forward on my account?

If you forward your mail, server-side filtering will NOT occur. One exception to this rule is explained in our forward policy.

Advanced users can choose to use client side filters instead of the server side filters.

Will client-side spam filtering interfere with the server side 'Junk Mail' filter?

Yes. Many email clients have spam filtering capabilities built into the software. Please be aware that any spam filtering options that you see in these email clients are not the same as the server-side spam filtering service provided by WiscMail. You should also be aware that the use of the client-side spam filtering options may interfere with the effectiveness of the server-side WiscMail anti-spam service. Please note that most current clients turn on the client-side spam filtering options by default.

What types of entries can I add to the Accept List, Block List and Mailing Lists?

For the Accept List and Block List, you can add any continuous, case sensitive, part of the From: header of a message. The From: header always contains an email address. Sometimes it contains a user's name as well as the address. The less specific you make the entry, the more likely it will match on unintended messages.

Why isn't my 'Custom Filter' working?

If you select "is" as your type of matching condition, then make sure that you type the exact, case sensitive, format of the header. If you only want to have the filter match on a portion of a header (such as an email address or a name) then use "contains" instead.

Make sure that you do not have any trailing spaces in the entry.

Are virus messages considered spam?

Yes. Messages that are infected by viruses that are known to be abusive in nature are deleted without notice to the sender or recipient. All other virus infected messages are disinfected and labeled as spam.

Are executable attachments allowed?

The WiscMail/WiscMail Plus servers will rename executable file attachments in all incoming and outgoing messages for security reasons. For more information, view WiscMail / WiscMail Plus - Executable Attachment Renaming

Are all the messages that I receive scanned for spam?

No. The following scenarios are trusted and not scanned for spam:

  • Messages filtered by a filter that appears above the Junk Mail filter will be delivered based on the highest filter, not the Junk Mail filter.
  • Message submitted from any WiscMail user destined to another WiscMail user (assuming no forwards are involved).

See Also:

Keywords:wiscmail plus web client spam filter virus faq rules   Doc ID:2054
Owner:Ara M.Group:WiscMail
Created:2003-06-09 18:00 CSTUpdated:2014-12-01 08:59 CST
Sites:DoIT Help Desk, DoIT Staff, WiscMail
Feedback:  8   19