Connection Refused

As of today, Post SMTP is generating error messages for every email sent through my contact forms. The Status in the log shows “Connection Refused”. In the transcript of each message, it just shows:

smtp:none:none://localhost:25

There is no indication in the exim_mainlog or maillog of the connection from Post SMTP. Also, Post SMTP successfully delivers the “Post SMTP email error” telling me that there was an error trying to deliver the contact form email. Finally, if I shut off the Post SMTP plugin, the contact form emails are delivered. This is happening on the latest version of Post SMTP and also the previous version with the default Post SMTP settings (no settings configured).

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