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About Spam

A Guide To Fighting Spam. 


 Spam is unwanted, unsolicited, commercial email. It is of growing concern because of its rapid proliferation on the Internet filling mailboxes and consuming bandwidth and time.

 Netwitz checks all email passing through our mail server against a series of anti-spam and anti-virus filters.  Even though we scan for viruses we

cannot promise to catch them all.  We strongly suggest that you maintain an up to date antivirus scanner on your computer. 

   All email passing through the Netwitz email system that is believed to be spam is marked

in the message header with the spam test that it failed and is delivered to the spam folder in the customers webmail mailbox.  It will remain in the spam folder for 3 days at which time it will be deleted to prevent your mailbox filling up.  You may move any or all of these messages to another folder to prevent them from automatically being deleted or you may download them with your pop3 client by creating an account with your username and a dash followed by spam (username-spam) and using your regular password.

   To take full advantage of the anti spam filters you will need to read the tutorial below to help you to establish rules on your email account. 

 What Netwitz does to help you, and what you can do to help yourself?

 Netwitz tests every email that comes to your account for viruses and the likelihood of spam. These tests scan for viruses and check the mail against a list of know spammers as well as looking for mail sent from mis-configured mail servers. When an email fails one of our tests for any reason, one of five actions takes place. 

  1. "Bounce", the email will not be delivered to you, and instead will send the message back to where it originally came from.

  2.  "Warn" appends a notice to the header of the email and it is delivered to you. The header is all of the addressing information the email needs to get from the sender to you. "Warn" is  applied to most of our tests and these warnings are what you will create your search strings from.

  3. "Delete" discards a message outright.  This action is reserved for messages which have the highest likelihood of being spam and cannot be bounced because of the nature of how they were sent.

  4. "Subject" may be applied to any message that fails the certain tests. When this happens, SPAM: is added to the subject of the message making it easy for you to identify.  

  5. Quarantine to your Spam folder.  In addition to the spam tests performed on each message, every message is checked against a series of rules created by the system administrator.  If it is caught by one of these rules a spam folder will be created in your webmail and the message will be delivered there. 

    To prevent mailboxes from filling up due to full spam folders, and ensure that mail continues to be received, messages contained in your spam folder will be deleted every 7 days.  If you find that an excessive amount of legitimate email is being sent to your spam folder and you need assistance you may contact support at .  We may be able to adjust your spam filters to accommodate your needs.

      Messages receiving the warn action will have an entry placed into the header.

The warnings usually say something like: "X-RBL-Warning: followed by the name of the test that it failed.  We suggest that you create filters that move messages that fail these tests to a separate folder called spam so that you can review what kind of messages fail the individual tests. Some of these tests catch more legitimate email than might be acceptable because the test is based on common,  frequently innocent mail server mis-configurations.  By sending suspected spam messages to a spam folder you will be able to see which tests are the most reliable for you.  You can then modify your filters to delete messages based on the test that you choose.  

 In addition to individual tests the Anti-spam test at Netwitz assigns a numeric value to each test using a unique weighting system. When a message fails enough tests that the combined weight exceeds the defined threshold the header will be marked accordingly. This is useful for messages that do not fail the dns or database tests but do fail a number of the configuration tests. A very accurate test may give out fifteen points, and a general test may only give three.   Many legitimate email messages will fail a number of configuration tests such as the bad headers or spam headers tests.  What the weighting system does is assign points to each test.  The more points that a message receives, the higher the likelihood that the message is spam.  The Weight 2 test is very aggressive and will catch a higher amount of spam than the Weight 10 test.  However the Weight 10 test will not catch nearly as much legitimate email and will catch email not marked as spam by other tests.Currently Netwitz marks email at the thresholds of 2, 5, 7 and 10.  Mail that fails with the threshold of 10 is automatically placed into the spam folder.

     In order to view your header in Outlook, Outlook Express, or Windows Mail, open the message then click file then properties. There will be a box that contains the header of the email. This is the section that most of our warnings are entered into. You can also view the header in webmail by clicking options and styles and choosing preferences.  Under message display options choose display full headers.  Then when you view the message just click on the Header link at the top of the message.

Creating Rules

For a description of the Rules page, see About Rules.

To create/edit a rule:

  1. Login to your webmail account at  In the lower left-hand pane, click the Rules icon (). The Rules page appears.
  2. Click the New button. The Add Rule page appears. If you wish to edit an existing rule, see Editing Rules.

Once you've navigated to the Add Rule page, creating the rule is a three-step process.

  1. Enter a name for this Rule. Enter a name for the rule in the Rule name text box
  2. Add the Rule Conditions.
    • Field. This column displays the rule fields available for editing.
    • Comparison. This column displays the comparison (either Contains or Does NOT Contain) available for editing.
    • Search Text. This column displays the message text the rule searches for, which can be edited.
    • Match Case. This column displays whether the rule is constructed to Match Case or not (Yes or No).
    • Edit. The Define Condition dialog appears when you click this button.
    • Delete. Click this button to delete the selected Rule Condition(s).
    • Move Up. Click this button to move the selected condition up in the rule's processing priority.
    • Move Down. Click this button to move the selected condition down in the rule's processing priority.
    1. Click the Add Condition button. The Define Condition dialog appears.
    • Where. Select to which part of the message the added/edited rule applies: From, Subject, Sender, To, or Body Header.
    • Comparison.
      • Contains. Select this option if you wish the message part to contain the text specified in the Search text box.
      • Does NOT Contain. Select this option if you wish the message part to NOT contain the text specified in the Search text box.
      • Search. Enter the message text for which you wish the rule to search.
      • Match Case. select whether or not you want the case of the text entered in Search to match or not.
      • Save. Click to Save your Condition.
      • Cancel. Click to cancel your condition and return to the Add Rule page

        If you wish to add multiple conditions to your rule, do the following:

    1. Add AND/OR. The Edit Conjunction dialog appears when you click this button. Select either AND or OR. Click Save to save your choice; click Cancel to cancel your selection. Click the Add Condition button to continue to add another Condition to your rule, as in Step 1 above. Repeat Step 1, 1a, and 1b until you have finished creating your rule with multiple conditions.

      Note: Editing options that are unavailable for the selected condition are grayed out.

  3. Set the action to take when conditions above are met.
    • Action Type. Set the action to take when conditions listed above are met. Options are: Move to mailbox, Forward, Delete, Copy, Bounce.
    • Target. Enter the name of the target mailbox that will receive messages that are selected by your rule.
    • Save and Close. Click this button to save your new Rule. The rule is displayed on the Rules page.
    • Cancel. Click this button if you to cancel your changes and return to the Rules page.

If you are receiving spam that is not detected and marked in the header you can create filters based on ip addressing information found in the header. You can also create filters based on words found in the subject or body like Mortgage or Sex.  We do not recommend initially choosing delete since good mail may be accidentally deleted. Instead watch your spam folder for several weeks and see which tests are catching the most spam and the least desirable email. You can then create delete filters

If you have one, Check your spam folder from  Netwitz Web mail periodically and delete the bad emails to ensure that you will have enough space for the email you want to get through Netwitz Will periodically delete messages from your spam folder to prevent your mailbox from filling up.  You should check your spam box periodically and remove any mail that you would like to keep and place it in another folder to keep from losing it.


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