Pop
Content
POP or Post Office Protocol is a technology used for downloading messages from an email server to your computer. Just like most other things on the internet, email too is based on the client-server model and POP is the language used in the communication between an email clients and a server.
Are POP and POP3 the same thing?
Yes! POP3 is actually version #3 of the Post Office Protocol and this means the technology has gone through a couple of iterations before finally arriving in its present form. Did you know that when someone sends you an email, it doesn't arrive directly at your computer? The message first comes to a computer that's connected to the internet 24/7 and is stored there. Such a computer is known as a web server and to receive email messages it runs a special program called the email server. Depending on the kind of access allowed, you can check your emails using a web browser or employ a dedicated email program (also known as an email client). Email clients are programs that let you send and receive email messages from your computer. There are several popular free email clients like Outlook Express, Windows Mail Vista, Windows Live Mail and Thunderbird. If you use Windows, you already have an email program pre-installed on your system - Outlook Express on Windows XP and Windows Mailon Vista. Some time back Microsoft released a new email client which they call Windows Live Mail meant to "replace" Outlook Express and Windows Mail Vista. Get step by step instructions on how to download Windows Live Mail and install it on your computer.
Importance and usage of POP
The POP technology is used to build a communication channel between an email client and a server. It sets rules for downloading email messages that are stored on an online hard disk to your local computer hard disk. Using POP you can download all emails to your computer and, thus, view them anywhere you want - even without an internet connection. Yes, an active internet line is required to download messages from the server but once they come to your computer, you can sever the connection. You'll appreciate the importance of POP if you have ever faced a problem in accessing email messages (even the old ones) from an online account such as Hotmail, Yahoo! Mail or Gmail. Maybe the net connection wasn't working properly, maybe you were at a location where internet wasn't available or maybe the email service was down... whatever. And frustration is what follows. Now imagine the brighter scenario of keeping a copy of all your emails on your computer using a using POP enabled email program. Agreed you'll still not be able to check for new messages but you at least have access to old ones.
Do all email servers use POP?
No - it depends on the service provider and the web server configuration. Typically, email accounts from ISPs (Internet Service Providers) and those you create on your web site come with POP access. Online email service providers like Yahoo! Mail, Hotmail, AOL and Gmail have different policies when it comes to POP access. For instance, you can enable POP on Gmail accounts for free - you can do this yourself. Yahoo! Mail charges you about $20 per year access your account through POP. For Windows Live Hotmail users, there is some good news finally; POP on Hotmail is gradually being rolled out - it's available only to subscribers in some countries at the time of writing and I hope it will soon be included on all accounts.
Why don't all email services allow POP access?
Well, since the protocol lets you to download messages to your computer via an email client, you'll have no need to checking your messages on the web based service. This means you would hardly ever log in to your online account and, thus, would not "pay" for your free access by either looking at the advertisements or, less so, clicking on them! All free web based email accounts, even Gmail, are supported by the advertising. The companies show these ads expecting subscribers to compensate the privilege of free access by checking out the sponsored products or services.
How do you access email through POP - Post Office Protocol?
As mentioned above, your email service should provide you with a POP access. Please check with them. Once you get a POP enabled email account, all you need is an email client that can use the Post Office Protocol. Windows users are lucky because a free email client is available on all versions. In fact, Microsoft has released the new Windows Live Mail email client which can be downloaded for free from their web site. Accessing emails through POP is a simple affair. You only need the username, password and the email server address. The incoming email server address is, typically, pop.THE-DOMAIN-NAME.com or simply THE-DOMAINNAME.com. For step by step instructions on using POP with Windows based email clients please refer the list below:
Setup new email account in Outlook Express Configure Gmail on Outlook Express Configure email account on Windows Mail Vista Add Gmail on Windows Mail Vista Setup Windows Live Mail email client Setup and configure Gmail on Windows Live Mail
FYI, the Post Office Protocol is employed only for downloading emails and goes hand in hand with SMTP or the Simple Mail Transfer Protocol which is used for sending emails. POP enabled email account can also be accessed via a web browser as long as the service provider has put up an interface (a graphical user interface, usually) through which the account can be managed.
Connected and disconnected modes of operation
When using POP, clients typically connect to the e-mail server briefly, only as long as it takes to download new messages. When using IMAP4, clients often stay connected as long as the user interface is active and download message content on demand. For users with many or large messages, this IMAP4 usage pattern can result in faster response times.
Header-only message retrieval
The POP protocol demands clients to download entire messages, whereas IMAP permits downloading the message headers separate from the actual message content. This makes "mail bombing", a malpractice where many large messages are sent to a single recipent, much less effective on IMAP than it is on POP, as the content of each message is only actually retrieved when the message is opened.
Multiple clients simultaneously connected to the same mailbox
The POP protocol requires the currently connected client to be the only client connected to the mailbox. In contrast, the IMAP protocol specifically allows simultaneous access by multiple clients and provides mechanisms for clients to detect changes made to the mailbox by other, concurrently connected, clients.
Access to MIME message parts and partial fetch
Usually all Internet e-mail is transmitted in MIME format, allowing messages to have a tree structure where the leaf nodes are any of a variety of single part content types and the non-leaf nodes are any of a variety of multipart types. The IMAP4 protocol allows clients to separately retrieve any of the individual MIME parts and also to retrieve portions of either individual parts or the entire message. These mechanisms allow clients to retrieve the text portion of a message without retrieving attached files or to stream content as it is being fetched.
Message state information
Through the use of flags defined in the IMAP4 protocol, clients can keep track of message state; for example, whether or not the message has been read, replied to, or deleted. These flags are stored on the server, so different clients accessing the same mailbox at different times can detect state changes made by other clients. POP provides no mechanism for clients to store such state information on the server so if a single user accesses a mailbox with two different POP clients, state information—such as whether a message has been accessed—cannot be synchronized between the clients. The IMAP4 protocol supports both pre-defined system flags and client defined keywords. System flags indicate state information such as whether a message has been read. Keywords, which are not supported by all IMAP
servers, allow messages to be given one or more tags whose meaning is up to the client. Adding user created tags to messages is an operation supported by some web-based email services, such as Gmail.
Multiple mailboxes on the server
IMAP4 clients can create, rename, and/or delete mailboxes (usually presented to the user as folders) on the server, and move messages between mailboxes. Multiple mailbox support also allows servers to provide access to shared and public folders. The IMAP4 Access Control List (ACL) Extension (RFC 4314) may be used to regulate access rights.
Server-side searches
IMAP4 provides a mechanism for a client to ask the server to search for messages meeting a variety of criteria. This mechanism avoids requiring clients to download every message in the mailbox in order to perform these searches.
Built-in extension mechanism
Reflecting the experience of earlier Internet protocols, IMAP4 defines an explicit mechanism by which it may be extended. Many extensions to the base protocol have been proposed and are in common use. IMAP2bis did not have an extension mechanism, and POP now has one defined by RFC 2449.
How to configure email clients
You can use either the webmail interface or an email client. Check our tutorial on how to use cPanel webmail. If you decide to use an email client, such as Microsoft Outlook Express, MS Outlook, Mozilla Thunderbird and Eudora, here are the settings you need:
Incoming mail server (POP3/IMAP server): mail.yourdomain.com Outgoing mail server (SMTP server): mail.yourdomain.com Or Host: mail.yourdomain.com Username: the full e-mail address. Example: [email protected] instead of you. Password: Assigned in cPanel -> Email -> Manage/Add/Remove Accounts. SMTP authentication must be enabled for the login to be successful.*
If you have your domain pointed to an external server and the MX record is resolving to one of the SiteGround servers use the server name as the Incoming/Outgoing mail server. You can also use secure authentication to your mail server.
Email ports
The POP3 port for inbound emails is 110 (995 if you want to use secured POP3) And the IMAP port for inbound emails is 143 (993 if you want to use secured IMAP) The SMTP port for outbound emails is 25 or 2525 (465 if you want to use secured SMTP)
Learn how to set your email clients to work with your webmail account:
Outlook express MS outlook Mozilla Thunderbird Mozilla Thunderbird 3 Mac Mail
Email protocols
What is POP3? Post Office Protocol version 3 (POP3) is a standard mail protocol used to receive emails from a remote server to a local email client. POP3 allows you to download email messages on your local computer and read them even when you are offline. What is IMAP? The Internet Message Access Protocol (IMAP) is a mail protocol used for accessing email on a remote web server from a local client. IMAP and POP3 are the two most commonly used Internet mail protocols for retrieving emails. Both protocols are supported by all modern email clients and web servers.
Main difference between IMAP and POP3: The POP3 protocol assumes that there is only one client connected to the mailbox. In contrast, the IMAP protocol allows simultaneous access by multiple clients. IMAP is suitable for you if your mailbox is about to be managed by multiple users. What is SMTP? Simple Mail Transfer Protocol (SMTP) is the standard protocol for sending emails across the Internet. SMTP uses TCP port 25 or 2525 and sometimes you can have problems to send your messages in case your ISP has closed port 25 (How to check if port 25 is open?). To determine the SMTP server for a given domain name, the MX (Mail eXchange) DNS record is used.
Are POP and POP3 the same thing?
Yes! POP3 is actually version #3 of the Post Office Protocol and this means the technology has gone through a couple of iterations before finally arriving in its present form. Did you know that when someone sends you an email, it doesn't arrive directly at your computer? The message first comes to a computer that's connected to the internet 24/7 and is stored there. Such a computer is known as a web server and to receive email messages it runs a special program called the email server. Depending on the kind of access allowed, you can check your emails using a web browser or employ a dedicated email program (also known as an email client). Email clients are programs that let you send and receive email messages from your computer. There are several popular free email clients like Outlook Express, Windows Mail Vista, Windows Live Mail and Thunderbird. If you use Windows, you already have an email program pre-installed on your system - Outlook Express on Windows XP and Windows Mailon Vista. Some time back Microsoft released a new email client which they call Windows Live Mail meant to "replace" Outlook Express and Windows Mail Vista. Get step by step instructions on how to download Windows Live Mail and install it on your computer.
Importance and usage of POP
The POP technology is used to build a communication channel between an email client and a server. It sets rules for downloading email messages that are stored on an online hard disk to your local computer hard disk. Using POP you can download all emails to your computer and, thus, view them anywhere you want - even without an internet connection. Yes, an active internet line is required to download messages from the server but once they come to your computer, you can sever the connection. You'll appreciate the importance of POP if you have ever faced a problem in accessing email messages (even the old ones) from an online account such as Hotmail, Yahoo! Mail or Gmail. Maybe the net connection wasn't working properly, maybe you were at a location where internet wasn't available or maybe the email service was down... whatever. And frustration is what follows. Now imagine the brighter scenario of keeping a copy of all your emails on your computer using a using POP enabled email program. Agreed you'll still not be able to check for new messages but you at least have access to old ones.
Do all email servers use POP?
No - it depends on the service provider and the web server configuration. Typically, email accounts from ISPs (Internet Service Providers) and those you create on your web site come with POP access. Online email service providers like Yahoo! Mail, Hotmail, AOL and Gmail have different policies when it comes to POP access. For instance, you can enable POP on Gmail accounts for free - you can do this yourself. Yahoo! Mail charges you about $20 per year access your account through POP. For Windows Live Hotmail users, there is some good news finally; POP on Hotmail is gradually being rolled out - it's available only to subscribers in some countries at the time of writing and I hope it will soon be included on all accounts.
Why don't all email services allow POP access?
Well, since the protocol lets you to download messages to your computer via an email client, you'll have no need to checking your messages on the web based service. This means you would hardly ever log in to your online account and, thus, would not "pay" for your free access by either looking at the advertisements or, less so, clicking on them! All free web based email accounts, even Gmail, are supported by the advertising. The companies show these ads expecting subscribers to compensate the privilege of free access by checking out the sponsored products or services.
How do you access email through POP - Post Office Protocol?
As mentioned above, your email service should provide you with a POP access. Please check with them. Once you get a POP enabled email account, all you need is an email client that can use the Post Office Protocol. Windows users are lucky because a free email client is available on all versions. In fact, Microsoft has released the new Windows Live Mail email client which can be downloaded for free from their web site. Accessing emails through POP is a simple affair. You only need the username, password and the email server address. The incoming email server address is, typically, pop.THE-DOMAIN-NAME.com or simply THE-DOMAINNAME.com. For step by step instructions on using POP with Windows based email clients please refer the list below:
Setup new email account in Outlook Express Configure Gmail on Outlook Express Configure email account on Windows Mail Vista Add Gmail on Windows Mail Vista Setup Windows Live Mail email client Setup and configure Gmail on Windows Live Mail
FYI, the Post Office Protocol is employed only for downloading emails and goes hand in hand with SMTP or the Simple Mail Transfer Protocol which is used for sending emails. POP enabled email account can also be accessed via a web browser as long as the service provider has put up an interface (a graphical user interface, usually) through which the account can be managed.
Connected and disconnected modes of operation
When using POP, clients typically connect to the e-mail server briefly, only as long as it takes to download new messages. When using IMAP4, clients often stay connected as long as the user interface is active and download message content on demand. For users with many or large messages, this IMAP4 usage pattern can result in faster response times.
Header-only message retrieval
The POP protocol demands clients to download entire messages, whereas IMAP permits downloading the message headers separate from the actual message content. This makes "mail bombing", a malpractice where many large messages are sent to a single recipent, much less effective on IMAP than it is on POP, as the content of each message is only actually retrieved when the message is opened.
Multiple clients simultaneously connected to the same mailbox
The POP protocol requires the currently connected client to be the only client connected to the mailbox. In contrast, the IMAP protocol specifically allows simultaneous access by multiple clients and provides mechanisms for clients to detect changes made to the mailbox by other, concurrently connected, clients.
Access to MIME message parts and partial fetch
Usually all Internet e-mail is transmitted in MIME format, allowing messages to have a tree structure where the leaf nodes are any of a variety of single part content types and the non-leaf nodes are any of a variety of multipart types. The IMAP4 protocol allows clients to separately retrieve any of the individual MIME parts and also to retrieve portions of either individual parts or the entire message. These mechanisms allow clients to retrieve the text portion of a message without retrieving attached files or to stream content as it is being fetched.
Message state information
Through the use of flags defined in the IMAP4 protocol, clients can keep track of message state; for example, whether or not the message has been read, replied to, or deleted. These flags are stored on the server, so different clients accessing the same mailbox at different times can detect state changes made by other clients. POP provides no mechanism for clients to store such state information on the server so if a single user accesses a mailbox with two different POP clients, state information—such as whether a message has been accessed—cannot be synchronized between the clients. The IMAP4 protocol supports both pre-defined system flags and client defined keywords. System flags indicate state information such as whether a message has been read. Keywords, which are not supported by all IMAP
servers, allow messages to be given one or more tags whose meaning is up to the client. Adding user created tags to messages is an operation supported by some web-based email services, such as Gmail.
Multiple mailboxes on the server
IMAP4 clients can create, rename, and/or delete mailboxes (usually presented to the user as folders) on the server, and move messages between mailboxes. Multiple mailbox support also allows servers to provide access to shared and public folders. The IMAP4 Access Control List (ACL) Extension (RFC 4314) may be used to regulate access rights.
Server-side searches
IMAP4 provides a mechanism for a client to ask the server to search for messages meeting a variety of criteria. This mechanism avoids requiring clients to download every message in the mailbox in order to perform these searches.
Built-in extension mechanism
Reflecting the experience of earlier Internet protocols, IMAP4 defines an explicit mechanism by which it may be extended. Many extensions to the base protocol have been proposed and are in common use. IMAP2bis did not have an extension mechanism, and POP now has one defined by RFC 2449.
How to configure email clients
You can use either the webmail interface or an email client. Check our tutorial on how to use cPanel webmail. If you decide to use an email client, such as Microsoft Outlook Express, MS Outlook, Mozilla Thunderbird and Eudora, here are the settings you need:
Incoming mail server (POP3/IMAP server): mail.yourdomain.com Outgoing mail server (SMTP server): mail.yourdomain.com Or Host: mail.yourdomain.com Username: the full e-mail address. Example: [email protected] instead of you. Password: Assigned in cPanel -> Email -> Manage/Add/Remove Accounts. SMTP authentication must be enabled for the login to be successful.*
If you have your domain pointed to an external server and the MX record is resolving to one of the SiteGround servers use the server name as the Incoming/Outgoing mail server. You can also use secure authentication to your mail server.
Email ports
The POP3 port for inbound emails is 110 (995 if you want to use secured POP3) And the IMAP port for inbound emails is 143 (993 if you want to use secured IMAP) The SMTP port for outbound emails is 25 or 2525 (465 if you want to use secured SMTP)
Learn how to set your email clients to work with your webmail account:
Outlook express MS outlook Mozilla Thunderbird Mozilla Thunderbird 3 Mac Mail
Email protocols
What is POP3? Post Office Protocol version 3 (POP3) is a standard mail protocol used to receive emails from a remote server to a local email client. POP3 allows you to download email messages on your local computer and read them even when you are offline. What is IMAP? The Internet Message Access Protocol (IMAP) is a mail protocol used for accessing email on a remote web server from a local client. IMAP and POP3 are the two most commonly used Internet mail protocols for retrieving emails. Both protocols are supported by all modern email clients and web servers.
Main difference between IMAP and POP3: The POP3 protocol assumes that there is only one client connected to the mailbox. In contrast, the IMAP protocol allows simultaneous access by multiple clients. IMAP is suitable for you if your mailbox is about to be managed by multiple users. What is SMTP? Simple Mail Transfer Protocol (SMTP) is the standard protocol for sending emails across the Internet. SMTP uses TCP port 25 or 2525 and sometimes you can have problems to send your messages in case your ISP has closed port 25 (How to check if port 25 is open?). To determine the SMTP server for a given domain name, the MX (Mail eXchange) DNS record is used.
