Ongoing SMTP connection errors so moved to alternative plugin

I’m afraid I have to give your plugin a bad review as in my experience it’s recently prone to regular intermittent connection errors as in the SMTP connect() failed error. It had worked great for many months on a customer’s site we manage but suddenly from about 3 months ago we started seeing intermittent, (but unfortunately also very regular) failures of automated emails being sent. On checking it was always an SMTP connect or authentication error – even though we had not changed the SMTP server settings at all and I was able to confirm the same settings worked sending emails from mail clients or testing via other means. I had made sure we were always using the latest available version of your plugin and did try the troubleshooting steps as at https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting but it made no difference. My hosting provider’s tech support could not explain it either. They eventually suggested I try a different SMTP plugin.

Two weeks ago I disabled your plugin and instead installed the WP Mail SMTP Plugin by Mail Bank. I configured it with the exact same SMTP authentication settings as before. Since then I have seen 100% success with emails being delivered every time. I’m afraid this clearly suggests to me a problem with your plugin.