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Email Forwarding Service
(INPUT) POP Server Properties

POP3 Connection Settings

This property tab is used to configure all POP related settings for the connector.


POP3 Host: Specify the hostname or the IP address of the POP3 Server. By default, the service will connect to port 110 (pop3), if you want co connect to an alternative port - specify the port number after a colon, as "server:port". (See SSL for more information)
SSL If the POP3 server requires SSL/TLS immediately in the authentication state when the connection is established, tick SSL after the host name. If this box is ticked, and SSL/TLS can't be established, then the service will disconnect from the server. For POP3 typically port 995 is used for SSL connections. No data will be sent or received until encryption has been enabled.
User: Specify the user name used to log on to the POP3 mail box.
Password: Specify the password for the POP3 mail box.


A POP server can support many different protocols for authenticating the user. Some are secure, using encrypted secrets/password. Some are less secure using obscured but not encrypted username/password and some are completely unsecured with username/password being sent in the clear. Poprep supports the most popular protocols used to connect to a POP Server. It also gives you full control over what protocol that is being used to authenticate to a particular server. Poprep takes advantage of native Windows API's for some of these protocols hence it's important that you run poprep on a supported operating system. Poprep has been tested on Windows 2000, 2003 and Windows XP. It has not yet been certified for Windows Vista, but it can be expected to operate successfully on Windows Vista.

Poprep can also detect if SSL/TLS is supported, and if so switch to an encrypted connection BEFORE it authenticates the user.

Some POP server are known to announce that is supports a particular authentication protocol, only to fail and disconnect if you attempt to use it. In those situations, you can enable verbose logging/debugging and Poprep will write the negotiation sequence to the log file, allowing you to see what protocol is being used, and if it is failing. You can then switch off that particular protocol, in favour of an other one. If at all possible, avoid using "Clear Text" or "LOGIN" unless used in combination with SSL/TLS.

Protocol Detection, two commands can be used to detect what authentication protocols are supported, and if SSL/TLS is supported. Not all POP3 servers support these commands, and most only support one of them. If none of the detection commands are supported, then Poprep will not be able to use the authentication protocols that requires detection either.

You must select at least one authentication method. If you enable many, or all protocols, Poprep will first attempt to use a more secure protocol, and if that fails it will fall back towards the less secure protocols. If one protocol fails, Poprep may disconnect from the server, and then reconnect trying one of the less secure protocols. In this situation, it's better to disable the protocol that can't be used, saving the time it takes to reconnect to the server.

Authentication Protocols:

(Clear Text)
Nearly all POP3 servers support this authentication protocol. Both the username and the Password is sent in clear text format.
APOP The Username is sent in clear text. The Password and a random string sent from the POP3 Server is hashed using MD5 and sent back to the server. - More secure that Clear Text.
LOGIN The Username and Password is obscured before it's sent to the POP3 server. Making it a bit mode difficult to see them for the novice. But they are NOT encrypted, so any one that know how to can very easily convert them back to clear text.
CRAM (CRAM-MD5) The Username is obscured and the Password and a random string sent from the POP3 Server is hashed using MD5 and sent back to the server. - More secure that Clear Text and APOP.
NTLM Reasonably secure. This is the same authentication mechanism as Microsoft are using between Windows/NT Systems.

Detection Protocols:

CAPA Detect if any of the following are supported: USER, LOGIN, CRAM, NTLM, MSN, SSL
AUTH Detect if any of the following are supported: USER, LOGIN, CRAM, NTLM, MSN
(Welcome) The welcome string sent by the POP3 server, indicates if APOP is supported.

SSL/TLS Encryption:

WANTED Use encryption if supported by the server. If not supported, or if we failed to enable encryption, we will continue to log on and download messages from the server.
REQUIRED We will attempt to negotiate a SSL/TLS connection with the POP3 server. If encryption isn't supported, of if we failed to enable encryption, we will disconnect from the Server.

Server Copy

Leave copy of Message on Server If enabled, the mail will not be removed from the pop3 server after it's been read.
Remove from server after (n) days If enabled, you can specify for how many days the message should be kept on the pop3 server until it's deleted.
Remove from server after delivered If enabled, the mail will be removed from the pop3 server, once it's been successfully sent on the the smtp server.


Poll Frequency

Poll every

Specify the interval (In Minutes) between each check for new mails.
NOTE: The current version of POPREP share a single thread for polling and sending emails. So even if you specify a poll frequency of once every minute, it may be longer between each poll.

Poll This Server

Use TOP Read the email from the server using the command TOP rather that the default of RETR.

Most POP servers marks the email as read and leaves it in the mail store when it's been read from a mail client. And when the server is polled again it continues to list it as being present util deleted.

But some systems will delete the mail from the store once it been read, yet other systems will leave the mail in the store, but it will NOT be listed when a mail client is requesting a list of mails. This applies to the GOOGLE email service.

In the first instance that means that even if you configured POPREP to leave a copy of the mail on the POP3 server, it will be removed when read, in the other instance, POPREP will NOT be able to remove the email at a later date, as it doesn't appear on the list of available mails, and eventually the inbox will be filled with old emails.

If you use POPREP with any system with this non typical behaviour, you will usually be able to achieve the desired result by enabling Use (the) TOP command to recieve the mails. Using TOP will not mark the mail as being read on the POP3 Server. Note that not all POP3 systems support this command.
Enabled If checked, then this connector is enabled.
NOTE: This controls both the POP3 and SMTP part of the connector.

Additional reading:





USER (Clear Text)