The purpose of a Spam trap is to find and block spammers. Setting up a spam trap involves using a seldom used email address and seeing if someone mails to that particular address. If someone mails to the address it's likely to be a spammer, because you never opted-in to their mailing list. Unfortunately, there are several different ways a spam trap can find it's way onto your user list, which will contaminate your list and have you wrongfully accused as a spammer. Spam traps commonly make it onto your list in the following scenarios:
Misspellings and Other Grammar Mistakes
A user accidentally makes a typo when spelling their email address on your contact form. The typo the user made now matches the same email as a spam tramp. Now if you mail to that address you will likely be reported as a spammer, because you are mailing to an address that never opted-in to your list.
The Email Address is Expired
An email address is no longer being used by a user and is expired. An anti-spam organization purchases the expired domain and is now using it as a spam trap. If this user is part of your list it's likely that you will be reported as a spammer upon mailing to them.
Purchasing a List
Purchasing a list of virtually unknown email addresses from another business or through a co-registration process, is a sure fire way to fall into several spam traps. There will likely be several users who will never be interested in receiving your mails using this method.
What are the best ways to keep spam traps off your list?
Cleansing your list of non-active subscribers routinely every six months will make a big difference immediately to your deliverability rate. Adopia's "scrubbing job" tool will allow you to strip your list inactive, potentially harmful subscribers for any time period of time and the automate feature will automatically "scrub" or cleanse your list of inactive subscribers automatically for the time interval that you set.
Checking the double opt-in box in your Adopia Account Settings is perhaps the best way that legitimate, interested subscribers will be added to your list.