I seem to get a fair amount of support email where users are having trouble with secure connections to the PMBx server in Windows. Here’s an example of the error. You need to make sure that your encryption settings are set to SSL and not TLS or Auto. First go to Account Settings as shown below.
Then select your email address like this.
Click Change… and you will see this.
Then click on More Settings… and you will finally get to the encryption settings for your email application.
From the image you see that TLS is selected. PMBx servers need to have SSL selected instead. Outgoing ports can be 994, 465, 587, and on Macintosh can be 586. POP ports can be 995 and IMAP ports can be 993.