I had been using gmail to send emails from my website for 2 years when all of a sudden my email functionality stopped working. When debugging the issue I found I was getting this error:
“The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required”
So I did some research… most sites had code to fix this however none of it worked form me, like enableSsl = true.
Then I accessed my email and at the top of the page of my gmail account I had a red suspicious login warning bar.
Now this is how I solved my issue:
Step 1:-
Login to your gmail account
Click “Was it you?” in the red top bar as in the image above.
Step 2:-
They will show you the suspicious login details such as date, IP, etc.
Click Recognize and Allow Access from this machine.
Step 3:-
Google will display the steps required as indicated below:
In the case your are accessing gmail from a website, go to the website and fill the contact form or whatever sends the email.
And just like magic, it should work and access will always be granted after that.
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