E-mail SPAM Filter Guide - Locked Addresses

Locked Addresses are designed to solve the following problem: You want to give out your E-mail address to someone, but you don't trust that person or organization not to turn around and give or sell it to others. You want an address that can only be used by the person or organization you give it to and not by anyone else. CanIt-PRO has a complete solution to this problem. However, it does require some administrative overhead before users can take advantage of the feature. If your administrator has not done the setup, then Locked Addresses will not be available for you.

How Locked Addresses Work
Creating A Locked Address
Viewing Locked Addresses
Editing A Locked Address
Deciding On A Lock Type and Violation Action

How Locked Addresses Work

When you create a locked address, CanIt-PRO generates a new random E-mail address, and associates it with your real E-mail address. The newly-generated address is in an unlocked state. Any E-mail arriving for that address will be delivered to your real E-mail address.

The very first time E-mail arrives for the new address, it locks on to either the sender address or the Domain. From now on, only that specific sender (or senders in that specific Domain) can send mail to the locked address. Anyone else who tries to send mail to the locked address will receive a "User Unknown" error.

There are two settings that affect how a locked address works:

The lock type can be one of Domain, Address or Unlocked. In the case of Domain, anyone in the same Domain as the initial sender can send to the locked address. If the lock type is Address, then only the initial sender (and no-one else) can send to the locked address. If the lock type is Unlocked, then the address always allows anyone to send to it. This may not seem very useful, but in fact, unlocked addresses are convenient for creating temporary E-mail addresses that are easy to rescind later.
The action if lock violated setting determines what happens if the lock is violated. (A lock is said to be "violated" if e mail for a locked address arrives from someone who is not allowed to send to that address.)
There are three options:
- (a) Hold mail in trap causes the violating E-mail to be held in your trap (regardless of what its SPAM score would be.) You should use this action if you use a locked address to post to a mailing list, because readers of the mailing list could legitimately try to E-mail you.
- (b) Reject mail causes the violating E-mail to be rejected with a "User unknown" error. This is the best setting to use if you're giving out an E-mail address to someone you don't quite trust.
- (c) Deactivate address is just like Reject mail, except it also deactivates the locked address so no-one at all can use it. You can use this setting if you really want to punish someone for giving out your E-mail address; if they give it out, then even they can't use it any more.

Creating a Locked Address

Click on "Rules" and then "Locked Addresses".
Click "Create a new Locked Address". The Locked Address Creation page appears.
Select a lock type (one of Domain, Address or Unlocked).
Select the action to take if the lock is violated (one of Hold mail in trap, Reject mail or Deactivate address.
If you like, enter a comment into the Comment: field to help you remember why you are creating the locked address. For example, if you're creating an address to paste into a Web form, you could put a little note about the Web site in the Comment: field.
Click Create Locked Address. Your new address is displayed.

You can cut-and-paste the address from the Web page into the Web form or any other window.

Viewing Locked Addresses

On the listing page:

Click Delete to delete a locked address. This completely removes the address from the system. Note that there is a very small chance that CanIt-PRO will generate the same address randomly in the future, causing confusion. However, the probability of this happening is less than one in four quintillion ( 1 4×1018 ) so you don't really need to worry about it. You're far more likely to be hit by lightning than to suffer from a Locked Address collision.
Click on the name of a locked address to edit it.
Enter appropriate values in the Filter Conditions fields and click Apply Filter to restrict which locked addresses are displayed. This lets you search for particular locked addresses. If you've entered meaningful comments when creating locked addresses, it can be very useful to search on the Comment: field.

Editing a Locked Address

Change the lock type by selecting a new value for the Lock type: field.
Change the violation action by selecting a new value for the Action if lock violated: field.
Manually change what the address is locked to by editing the Locked to: field. If you make the Locked to: field blank, then the address reverts to its pristine unlocked state.
Activate or deactivate the address by setting the Active: field to Yes or No. If you deactivate a locked address, then any mail sent to it is rejected with a "User unknown" error.
Change the comment by editing the Comment: field.

To make your changes take effect, click on Submit Changes. The bottom part of the Locked Address Editor shows the history of the locked address.

Deciding on a Lock Type and Violation Action