SMTP uses a standard port which is 25 so there isn´t an option to add or change the port, if your application uses a port other than port 25 then it will not be compatible.
The following instructions provide an example of how Email Settings should be setup, the default port used is 25(D-Link DIR-660 as example).
Step 1: Log into the router.
For the DIR model routers, the Email Settings can be found under the TOOLS tab.
Step 2: Put a check box in Enable Email Notification.
Step 3: In the field From Email Address: put in an address where you would like the email to show from and in the To Email Address: put where you would like the email to be sent. If your server requires authentication put a check in the box Enable Authentication: and enter the required information for Account Name: and Password:
Step 4: Finally, you can have the log emailed to you when it is full by checking the On Log Full: option and/or use a schedule that was previously created to email the log to the email address that was provided.
