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+ | ======SMTP -> General tab====== | ||
+ | This page is reached from [[Services]] -> [[SMTP Server]], then the **General** tab. | ||
+ | This page lets you set general settings for the SMTP service component of VPOP3. The SMTP service is how users send outgoing mail, and how incoming SMTP messages arrive. | ||
+ | |||
+ | ====Service Name==== | ||
+ | This sets the display name of the SMTP service in VPOP3. Usually this is set to **SMTP Server**. There is usually no need to change this unless you have VPOP3 Enterprise and choose to create extra SMTP services with different settings. | ||
+ | |||
+ | ====Bindings==== | ||
+ | The service **Bindings** are which IP addresses & ports the VPOP3 SMTP service will listen on for connections. The default is for it to listen on any available IP address on port 25 which is the standard port for SMTP transmission. | ||
+ | |||
+ | Press the **[[Edit Bindings]]** button to change the bindings. | ||
+ | |||
+ | ====Encryption==== | ||
+ | The **Encryption** option tells VPOP3 what sort of encryption should be used on SMTP connections to VPOP3. This option is only available in VPOP3 Enterprise, if an [[how_to: | ||
+ | |||
+ | The three options are: | ||
+ | * None/TLS - in this case VPOP3 supports TLS encryption, but will also allow unencrypted sessions from the email client | ||
+ | * TLS - VPOP3 requires TLS encryption, and will not allow unencrypted sessions | ||
+ | * SSL - VPOP3 requires SSL encryption | ||
+ | |||
+ | [[faq: | ||
+ | |||
+ | ====Bandwidth Throttling==== | ||
+ | The **Bandwidth Throttling** setting lets you set bandwidth throttling options for this service. For more details, [[http:// | ||
+ | |||
+ | ====Require SMTP Authentication==== | ||
+ | If this option is checked, then VPOP3 will require users to authenticate when sending mail via VPOP3. This applies to all connections, | ||
+ | |||
+ | In most cases nowadays this option is recommended to be enabled, especially if you are going to be wanting users to send mail from across the Internet (eg from mobile phones etc) | ||
+ | |||
+ | VPOP3 supports both 'AUTH LOGIN' and 'AUTH CRAM-MD5' | ||
+ | |||
+ | So that incoming SMTP mail does not require authentication, | ||
+ | |||
+ | ====Require POP3 then SMTP authentication==== | ||
+ | This option enables an [[wp>POP before SMTP|alternative method of SMTP authentication]]. ' | ||
+ | |||
+ | You can tell VPOP3 how long to allow between the POP3 login and the SMTP connection starting. The default is 5 minutes. | ||
+ | |||
+ | If you enable both **SMTP authentication** and **POP3 then SMTP authentication**, | ||
+ | |||
+ | ====Require Encrypted authentication==== | ||
+ | If this box is checked, then VPOP3 will only accept an encrypted authentication method. This could be CRAM-MD5 authentication, | ||
+ | |||
+ | ====Do not require SMTP authentication for internal/ | ||
+ | If this box is checked, then incoming or internal mail does not need to be authenticated, | ||
+ | |||
+ | ====SMTP Anti-Relay Protection==== | ||
+ | **This should be usually set to Check Client IP Address**. | ||
+ | |||
+ | This option has other methods which are still available due to historical reasons, but the **Check Client IP Address** option is the safest, along with good IP Access Restriction settings. | ||
+ | |||
+ | Email relaying is the name given to the act of sending a message to a server for that server to send on to another server. You would usually want to allow your local users to do this, and anyone else not to be able to do it. | ||
+ | |||
+ | * **No Checks** - if this option is chosen, then VPOP3 will restrict who can access the VPOP3 SMTP service at all using the IP Access Restrictions. Anyone who can access the VPOP3 SMTP service can relay mail through VPOP3. This can occasionally be useful if you trust everyone who you want to be able to access the VPOP3 SMTP service. Do //NOT// use this if you allow incoming SMTP mail to arrive from any server. | ||
+ | * **Check from LAN** - if this option is chosen, then VPOP3 will allow any IP address which is NOT linked to a dial-up adapter to be able to relay mail through VPOP3. This was useful in the days when people used dial-up adapters to connect to the Internet, but now it is rarely useful. | ||
+ | * **Check FROM address** - if this option is chosen, then VPOP3 will allow people to relay mail through VPOP3 if the FROM address matches a local email address. Since this is extremely easy to forge, it is no real protection against unwanted relaying | ||
+ | * **Check Client IP Address** - if this option is chosen, VPOP3 will allow ALL IP addresses to send mail to local users, but only those IP addresses listed on the IP Access Restrictions tab will be able to relay mail. This is most useful as it will protect against unwanted relaying, whilst also allowing incoming SMTP to work. | ||
+ | |||
+ | ====Maximum Message Size==== | ||
+ | This sets the maximum size, in bytes, of messages which can be sent through VPOP3. | ||
+ | |||
+ | We do not recommend using a value over about 50,000,000 bytes, as that can cause issues for current versions of VPOP3. | ||
+ | |||
+ | Email in general was not designed for excessively large file transfers, and most mail servers will reject mail over between 20MB and 50MB (some will reject mail over 5MB). | ||
+ | |||
+ | Note that when sending binary attachments such as images, Word documents, etc, that the attachment will typically grow by about 33% due to the [[wp> | ||
+ | |||
+ | ====Reject unrecognised local recipinets==== | ||
+ | If this option is checked, then VPOP3 will send an SMTP rejection response if someone tries to send a message to an unrecognised local user. | ||
+ | |||
+ | If this option is not checked, then VPOP3 will accept the message, and then send a message back saying the message could not be delivered. This is not recommended as it can cause ' |