Can't send outgoing email - How to Change Email SMTP Port

Many ISPs are now blocking port 25. If you are unable to send email but are able to receive, you may need to change your outgoing SMTP server port.

Here are the related instructions for the most popular email clients:

 

Thunderbird

To change the outgoing mail port from 25 to 587:

1. Launch the Thunderbird mail client
2. Drop down the Edit menu, and choose Account Settings
3. Click Outgoing Server (SMTP)
4. On the right hand side select the server to modify and click Edit
5. Change the port number from 25 to 587
6. Click OK
7. Restart Thunderbird

Microsoft Outlook and Outlook Express

To change the outgoing mail port from 25 to 587:

1. In Outlook, drop down the Tools menu
2. Choose Accounts or Email Accounts
3. View or change existing e-mail accounts should be marked
4. Click Next
5. Select the account and click Change
6. Select More Settings
7. In Outlook Express, drop down the Tools menu
8. Choose Accounts
9. Select the account and click Properties
10. Click on the Advanced tab
11. Change the outgoing mail from port 25 to port 587
12. Make sure that the box that says This connections requires a secure connection(SSL) is NOT checked
13. Click OK
14. Restart Outlook

Mac Mail 10.5+

To change the outgoing mail port from 25 to 587:

1. Launch Mac Mail
2. Drop down the mail menu, and choose preferences
3. Select the email account to modify under accounts .
4. Beneath Outgoing server (SMTP) click on the drop down bar and select "Edit SMTP server list...".
5. Click on your desired Outgoing server and then click advanced.
6. Select option for custom port and type in 587.
7. Click OK
8. Restart Mac Mail

Eudora for Windows

Eudora has chosen to hide the Port change option in version 6.0 and up, making it more difficult to make this change. If you have purchased Eudora, we would suggest contacting them about making this option available by default again. To enable changing ports:

1. Navigate to your Eudora install directory.
2. Look in the Eudora directory for the directory "extrastuff".
3. In this directory is a file named "esoteric.epi". Drag (copy or move) this file into the main Eudora directory. There will now be options extra listed, including a Ports page.

To change the outgoing mail port from 25 to 587:

1. Launch Eudora
2. Drop down the Tools menu, and choose Options
3. Click on Ports
4. Change the port from 25 to 587
5. Click OK
6. Restart Eudora

Eudora for Mac

As above, Eudora has hidden the ports option in version 6.0 and up. If you have purchased Eudora, we suggesting contacting them about this, as there is no reason to make this difficult. To change the outgoing mail port from 25 to 587:

1. For version 6.0 and up, quit Eudora and look in the Eudora Application Folder for the folder "Extras". In this folder is a file "Esoteric Settings". Drag this file into the "Eudora Stuff" folder,
2. Launch Eudora
3. Drop down the Special menu, and choose Settings
4. Click on Ports and Protocols
5. Change the port from 25 to 587
6. Click OK
7. Restart Eudora

Entourage

To change the outgoing mail port from 25 to 587:

1. Launch Entourage
2. Drop down the Tools menu, and choose Accounts
3. Click on Mail , and go to Properties
4. Click Advanced Sending Options
5. Make sure the box that says "This POP service requires a secure connection" is unchecked
6. Check the box that says "Override default SMTP port:" and enter in port 587
7. Click OK
8. Restart Entourage