Hey @theorygeorgiou
Thank you for leaving us a review and we are sorry to hear about your Cpanel/Apache server going down after attempting to use the Google mailer.
I checked your support thread here and can see that the issue was apparently related to the redirect URI not being correct.
That really is a strange occurrence, because we haven’t received any other recent reports about this and I am having a hard time reproducing the issue.
Generally speaking, if the redirect URI was incorrect (or any other issues were to occur), an error would appear in the WP Mail SMTP settings indicating what is the most likely reason for the issue. Then it would just be a matter of correcting that issue.
The most likely culprit for the downtime is either WP Mail SMTP was not installed correctly or there was potentially a conflict with another plugin/theme or even your server settings. Unfortunately, we wouldn’t be able to determine the specific reason without testing your website specifically.
On your end, if you’re interested to confirm if the issue is reproducible, you could generate a staging website and insert the incorrect redirect URI when setting up the Google mailer, to see if the issue occurs on the staging website (this won’t affect your live website).
I also see that you were viewing a WPBeginner article, which is accurate, but just for future reference, to find the latest documentation on any of our mailers, we would recommend checking WP Mail SMTP mailer documentation here.
Lastly, please know that this isn’t the general behavior of WP Mail SMTP and we are truly sorry that this issue occurred while using it.
