Anonymous remailers are a privacy tool to send emails anonymously, without encoded information about the true email origin. Remailers were originally developed by coders concerned about the government’s ability to intercept and read emails sent over conventional mail servers using the Post Office Protocol (POP).
An anonymous remailer service takes the original email and strips out certain information used to identify where the email originated from and who sent it. When you type in an email in software such as Outlook or Outlook Express, it automatically inserts identifying information is what is called a “header.” This is not immediately visible when you read the email but if you check the properties or the raw code of the message, you’ll be able to see it. An anonymous remailer removes all of this information and inserts fake data before delivering it to the recipient.
The other way email origins can be tracked is using the IP (Internet Protocol) addresses that are attached to the email or logged when it transfers through a relay server. Anonymous remailers again insert fake information and does not use or store transaction logs about the message’s sender. In addition, many services allow the use of “chain” remailers to further protect the sender’s privacy. Chain remailers use two or three anonymous remailer servers with fake IP addresses that make’s it virtually impossible to track.
 Types of anonymous remailers
There are four types of remailer services currently available on the Internet.
A Pseudonymous remailer, or nym server, is the most basic of the four and simply removes the header and original email address and replaces it with another untraceable email address. It is delivered to the recipient and allows them to respond to the original message using the inserted email address.
A Cyberpunk remailer strips both the headers and senders before delivering it to the recipient. Fake information is inserted to further protect the users identity. This type of remailer quite often allows the sender to encrypt the message using the PGP (Pretty Good Privacy) protocol and automatically decodes it before delivering it to the recipient. Using encryption makes the message unreadable should it be intercepted during its relay to the final destination.
Mixmaster remailers use downloadable software for the sender to use when creating messages to be sent through their service. It alters the header and sender information before using its servers to deliver the message to the recipient anonymously.
Mixminion remailers are the latest development and extend the capabilities of Mixmaster remailers. It takes the message and breaks it down into multiple encrypted packets of information in a uniform size before sending it over the Internet. Once the server receives it, it is sorted and decoded before delivering it to the recipient.
 Remailer caution
The only way to completely ensure that your email is untraceable is using a service that does not allow replies to be sent back to you. If you do require this function, the remailer must use some sort of tracking system to ensure you receive the email. It generally stores the information in a list and assigns you a unique identifying address such as email@example.com. When it receives a response to the message sent, it consults the list and forwards it back to you.
Before selecting a remailer you need to decide whether you require one-way or two-way communication and find a service that suits your needs. Other factors to consider include the location of the anonymous remailer company and whether the jurisdiction permits seizure of equipment or operating records. The history of the service, its security measures and its reputation are all other leading things to consider when selecting an anonymous remailer service. Consult forums or perform search engine searches to locate detailed and unbiased information on the services you may be considering.