Free pop3 software for linux

pop3spam is a POP3 client which connects to a POP3 server and deletes unsolicited mail. If a message has been identified as unsolicited, it can be deleted directly from the POP3 server without the need to download it first.

Eventually your normal mail-retrieval utility (e.g. fetchmail) can gather all (cleaned) mail as usual. The program is intended for people with low bandwidth. Its very annoying if you first have to download lots of large messages just for the sole purpose of deleting them afterwards because your local spam filter debunked them as spam. Its also annoying to download very large messages (attachments) at all.

pop3spam doesnt use any hard wired regular expressions so it should basically work with any recent version. For information about the configuration and use of pop3spam, take a look at the man pages pop3spam(1) and pop3spamrc(5). A sample configuration file exists in the directory doc/ in the source tree.

Perl Pop3 is a POP3 server fully implemented in Perl.
The advantages over other POP3 servers are that it is not a memory hog, and can be used to connect to databases for authentication.
Also, its code is easy to extend for any other uses, like POP-before-SMTP and extended logging.
Main features:
- Does not read the mailbox into memory, it reads what it needs as it processes the mailbox, so its memory requirements are low.
- Most email delivery is just printing out to the client; this is done in a fast and efficient way.
- It uses the systems users in the default unix way, but it can be changed to read users off a database (using DBI/DBD). It is prepared to use the database right away and can be extended or configured to use existing systems.
- It can be use to solve the smtp authentication via popauth or relay-domains (with sendmail) so users can be permitted to send smtp mail after pop3 authentication. This has been an effective solution for roaming users.
- Logging can be extended beyond the use of text files to any other method available in Perl, including database systems.
- Also, security is not an issue, as input is strictly controlled.
Using an easily modifiable daemon as part of a e-mail solution can be of great advantage over other existing systems in other languages. Further development will also try to incorporate more easily configurable extensions and plugins, so rapid deployment and extensibility is achieved.
Installation:
For installation instructions and configuration please see the INSTALL file. For more detailed information, consult the DOC file.

wmMultiPop3 is a WindowMaker dockapp, written by me, Daniel Sundberg, which checks one or more pop3-accounts for new mail.

Its based on wmPop3, written by Scott Helden. Ive added support for multiple pop3 accounts (a few while-loops and some changes in the config-file parsing routines).

pop3.proxy is a POP3 e-mail proxy. Recently I added spam and virus scanning. It also supports (on Linux platforms) transparent redirection.
Enhancements:
- Added clamav version to e-mail header.

POP3 Virus Scanner Proxy is a full-transparent proxy daemon which scans all mails for viruses using third party scanners (built-in support for AVPD and Trophie).

You have to set up a port redirection in the linux-netfilter (iptables) so that all connections from e.g. inside your office to any POP3 server outside in the world will not leave your router, but come a local port, on which POP3VScan listens. POP3VScan receives from the linux kernel the original destinations of packets (the POP3 server outside in the world) and will connect to them.

All data we receive from the client will be sent to the server, and vice versa. With a little enhancement: we parse the neccessary parts of the POP3 protocol and when an email is sent from the server, we store it into a file, invoke a virusscanner and send it if it is good, or we just replace it with a virus notification. It should be possible to use all scanners using the scannertype=basic. Also POP3VScan provides scannertype=avpd for high-speed scanning using Kaspersky Anti-Virus for Linux, every C programmer can easily adept other scan-daemons (trophie, sophie, antivir, ...).

Neither the client nor the server has to be configured, none of them will take notice that theres a mailscanner (except the client when he gets a virus notification or if he looks into the header, and the server gets our ip as source).

yaspi (Yosis Anti-Spam POP3 fIlter bot) is a POP3 mail-scanner specifically made to combat mail bombings caused by viruses (i.e. Swen). It connects to the POP3 server, inspects the messages, and deletes the infected ones by itself automatically without ever downloading them.
yaspi most interesting feature is that it can automatically send abuse reports to the ISPs where the mails were originated. This way, most infected machines will be either disinfected or disconnected from the Internet (and so, sending infected mails!).
Main features:
- its free, distributed under the GNU GPL
- runs under Windows and Unix/Linux (maybe under Mac OS X, but untested)
- virus detecting rules are fully customizable
- integrated with Ricochet to send abuse reports
Enhancements:
- yaspi was killing its own messages, new rule added to let them pass
- new GUI available, still alfa, have several know bugs (but its not going to corrupt your mailbox, I hope!).

popa3d project is a tiny POP3 daemon.
It is designed with security as the primary goal. You can read more about its design, check out the change log, or download a popa3d tarball (the latest stable version is recommended) and refer to the documentation inside.
Enhancements:
- A couple of optimizations specific to x86-64 have been applied to the included MD5 routines.

lollipop is a POP3 server that is almost RFC 1939 compliant. lollipop main goal is speed, since it is designed for users who store very large numbers of messages (>4000) on the server. It only supports the maildir storage format.
This is an almost rfc1939 compliant POP3 server. The main goal of this program is the speed, especially if you have many mails in your maildir (>4000) and you want to store your mails on the server.
I created this program to provide a solution for my problem. I have a small server in my house and this collects my emails from my addresses (fetchmail, exim local delivery). I have a very good backup system for this machine, powered by dirvish. I have two desktops and a laptop computers. I want to store all of my emails (over 6000) on the server in maildir - mainly because this is an archived machine.
I tried to use IMAP, but unfortunately I found it slow even on fast ethernet LAN. I switched to POP3 with leave on server option but the statistic step was very-very slow. On my laptop I got timeouts before the statistic step done so its impossible to use this method on this slow machine.
Finally I decided to write a special POP3 server for this task. Poppy has memory and it reports as new mail only the new mails after the last download for that location. Its supports only maildir because for this solution, the mailbox isnt optimal. Your maildir must be in ~/.maildir if you use maildir with other name, create a link to it.
Configure: change the LAN address to your LAN (for example 192.168.1.1) in the beginning of the script.
Usage: just start it in the background. (./lollipop.pl &) and make sure not using another pop3 server.
Enhancements:
- CAPA in AUTH state was fixed.