Ports are the virtual endpoints of a network connection. All kinds of networked programs use the ports on your device to connect with the internet, including the Bridge.
The Bridge uses ports 1143 and 1025 by default. But sometimes one or both of these ports are already in use by another application, such as voice over IP, streaming media apps, another email service, etc. If that happens, you will see a “port already occupied” error.
The error message may appear before you configure your email client or at any point afterward if another app begins using the Bridge ports. The first step to resolving this issue is to change the port numbers used by the Bridge.
Changing port numbers in the Bridge
To assign the Bridge new port numbers, navigate to Settings -> Advanced settings -> Change SMTP/IMAP Ports.
From there, you can increase the port number by one (i.e. 1144 for IMAP / 1026 for SMTP).
If you receive the error again, continue to increase the port numbers incrementally until you no longer receive the error.
Updating port numbers in client settings
If you have not yet gone through the process of configuring your email client, follow the instructions provided for your client here. The client configuration will automatically identify the ports the Bridge is using. There’s nothing more you need to do.
However, if you have already completed client configuration, then you will need to update the ports in your client settings. This process is slightly different for each client.
In Thunderbird, right click on the account address on the left side. Select Settings -> Server settings. There you can change ports.
In Outlook, click on File -> Account settings, then select the your email address and click Change, go to More Settings -> Advanced, there you can change ports.
In Apple Mail, since this step is configured automatically, you’ll need to first change the ports in the Bridge app via Settings -> Advanced settings -> Change SMTP/IMAP Ports. Then set up your account with Apple Mail by clicking on Bridge. Under your account username, click on Configure Apple Mail and the port numbers will be updated automatically.