The ports Windows Live Mail uses for a particular email account is determined when you first setup the account, but that can be changed later on. A few years ago, internet service providers ("ISPs
") started blocking outgoing port 25, at the time the standard port used to send emails using POP3, because it was abused by spammers. In those days, many email providers allowed you to send unauthenticated mail - that meant that just by knowing a person's email address, you could send messages from their account - crazy, right? Fortunately, that's changed now. When that changed, people were scrambling, trying to figure out why they could no longer send emails. All they had to do was use another outgoing port. In this tutorial, we'll show you how to do just that for Windows Live Mail.
FYI - what is a "
port number"? In computer networking terms, a port is just a piece of software instruction that determines how a program can connect to an IP address (a unique number that identifies a computer on a local network, or on the internet). When it comes to email servers, the port number tells Windows Live Mail how it should talk to your webmail provider's server.
Once you are inside Windows Live Mail, click on the "Windows Live Mail" menu (it's the dropdown arrow near the top left corner of the main window). Then, select "Options > Email accounts" . The "Accounts" popup will open, listing all the accounts currently set up. Double-click on the one whose port you want to change. (This is a shortcut to clicking on the account to select it and then clicking on the Properties button.) 
Note: if you're dealing with a Hotmail / Outlook.com account, you won't be able to change the incoming or outgoing ports, because Microsoft (creator of both Windows Live Mail and Outlook.com) uses a proprietary protocol called DeltaSync to allow the email program and webmail service to "talk" to one another, notPOPorIMAP- so, no configurable port settings for those accounts! Depending on your changes, it might be easier to start over and setup the email account from scratch - learn how to add Gmail, Hotmail / Outlook.com, Yahoo Mail, or AOL.
For all other types of email accounts, click on the "Advanced" tab: it will show the two "Server Port Numbers". If it isn't visible, it's some kind of Microsoft email account. 
The port you choose depends on three things: the ports supported by and/or recommended by the webmail provider (Gmail, Yahoo Mail, AOL Mail, etc.) The protocol you are using to connect to that account (POP3 or IMAP). And whether a secure connection is used to retrieve messages or send them (TLS and SSL - Windows Live Mail only mentions "SSL", but both encryption models are supported). The screenshot on the left shows the default port settings for Gmail, using IMAP (Google supports both POP3 and IMAP).
The "Outgoing mail (SMTP)" port number is the one used when you send messages from Windows Live Mail. The "Incoming mail (IMAP or POP3)" configures the connection when Windows Live Mail tries to download messages / message headers from the server. With SSL / TLS, the default port numbers are 465 (outgoing) and 995 (incoming). With plain-text (unencrypted), the standard ports are 25 (SMTP / outgoing) and 110 for incoming POP3, and 143 for incoming IMAP.
Important: if you are getting some kind of port25error, remember that your ISP has probably disabled it. Port 25 blocking has become common practice. Here are some port numbers you can often use instead:587or2525. If you have a custom setup with port forwarding enabled on the router, keep that in mind.
In general, don't click on the "Use Defaults" button: each webmail provider has its own quirks. If you do, as a shortcut, make sure that everything matches!
A single mismatch in port/protocol combo, or security options can prevent you from sending or receiving mail!
The same function for the same protocol requires a different port number, depending on the whether the connection is encrypted or not. Make sure that SSL is checked or unchecked (whichever one you need), and that you entered the corresponding port numbers. Click OK to save your new port settings and encryption preferences. SSL is best (it means your username and password are sent encrypted/scrambled), but ultimately follow what your mail provider is recommending. 
Tip: if you are switching from unsecured ("plain-text
") authentication to secure (SSL/TLS), check those checkboxes first, because they'll automatically overwrite whatever value you have inside the incoming/outgoing port number text boxes. Then, manually type over the new port numbers you want to use.Click on the Close button to return to Windows Live Mail. The new ports and SSL settings take effect immediately, so if you had issues sending or receiving emails, those problems should be fixed the next time you click on the "Update All" button in the title bar or the Send/Receive button in the ribbon, and the next time you send or resend a message! 