Free what is pop3 software for linux

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.

WMPop3 is a Window Maker dockable I wrote which will inform a user on how many messages are currently in thier pop3 mail box.

WMPop3 when first executed will check if there is a .wmpop3rc file in the users home directory, it will create this if it can not be located. This file must be edited and the following fields must
be changed :

1) popserver - this is the name of the pop3 server.
2) port - this is the port the pop3 server is on.( default 110)
3) username - users pop3 login name.
4) password - users pop3 login password.
5) autochecking - This allows to disable or enable auto mail checking. 1 enables, 0 disables
6) mailcheckdelay - Number of minutes, before checking mail. (default = 10 minutes)
7) mailclient - this is the mail client you use to send/retrieve messgaes(default pine)
8) viewallmessages - This allows for alternating mail views, 0 shows unread and read messages, 1 shows only unread messages.

WMPop3LB is a multi POP3 accounts mailbox checker. It can connect to up to 6 POP3 accounts to check if you have mail, get the "From:" and "Subject:" header fields of each mail and display them in a 7 lines window.
Messages can be deleted directly off the servers by selecting the mails to delete and clicking the "delete" button.
Main features:
- up to 6 different pop servers / accounts.
- displays "From:" and "Subject:" fields for each mail.
- displays number of unread messages or total number of messages, per account
- different autochecking intervals for each pop account
- can delete mail directly off the server
- can launch a command for each new mail received, for each selected message or for each server.
- very verbose interface
Enhancements:
- fixed a bug in pop3WriteOneMail: the first line of a received buffer was always removed, so the received mail was incomplete and corrupted.

WMpop is a Window Maker DockApp for monitoring a local (mbox format) or POP3 mailbox. WMpop project displays:
- number of mails in the mailbox (or unread mails if checked in the preference screen),
- a scrolling text with the email address of the senders (only for local mailbox for the moment),
- and a status led, indicating mail checking progression and errors.
WMpop can be configured via a graphic interface written in GTK+. The configuration interface let you define parameters of your POP3 server, and let you personalize the app (changing icons or sound and choosing an external command to launch on demand).
It is internationalized, with French translation. You can also run several instances of the program of different mailboxes (remote or local).

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.

htsneak is a general-purpose HTTP tunnelling utility written in Python. It can be used for accessing external Internet resources from behind a firewall, through an HTTP proxy. It comes with a built-in proxy server that tunnels data through an HTTP proxy to external servers for pop3, imap, smtp, ymsg, etc.

Installation is very simple. Unzip the archive into your prefered installation directory.

Twisted Mail project provides client and server implementations of SMTP, POP3, and IMAP4.
These differentiate themselves from the Python standard library implementations both by presenting a much higher-level, easy-to-use interface and in their server components, which allow the implementation of custom servers for each protocol without dealing with protocol-level issues.
Twisted Mail includes a simple demonstration email server which accepts messages over SMTP, stores them in a Maildir arrangement, and can serve them to clients over POP3.
Enhancements:
- The IMAP4 client now properly quotes usernames and passwords when necessary.
- It also handles unsolicited FLAGS responses.
- The IMAP4 server can now parse multiple literals in a single command and to FETCH requests with multiple BODY parts.
- A bug where Deferreds returned from IMAP4 client methods would not receive connection lost notification has been fixed.
- Startup time on OS X has been improved.
- The SMTP server has been sped up.
- The POP3 mailbox API has been expanded to allow Deferreds to be returned in some cases.