Error 400: invalid_request

I have successfully configured a few Google Workspace accounts with Fluent SMTP until now and never had an issue. But this morning I got the same error. I wonder?if did anything changed on the Google side?

Yep, same problem. Suddenly, stopped working. When I try to authenticate token, get error

Authorisation Error
Error 400: invalid_request

You can't sign in to this app because it doesn't comply with Google's OAuth 2.0 policy for keeping apps secure.

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redirect_uri: urn:ietf:wg:oauth:2.0:oob

Yes, same issue here. First time install. Not… encouraging. Anyone figured this one out?

Yep, I also got this problem when I click the “Authenticate with Google & Get Access Token” button. That issue is still happening.

Same for me, have configured multiple gmail account in the past for FluentSMTP, and now it get stuck for the same reason at the same step ??

For those who are interested, I personally solved it by using Post SMTP plugin instead of FluentSMTP. I think they use a different way to connect to Google Account but it works. I hope I’m not stepping on the FluentSMTP team’s toes here. Overall, I think they are doing a great job with all their plugins (we’ve set up some of their other plugins for clients) but I had to resolve it for the client fast, and I was left with no options.

Hi,

Sorry, we missed your ticket earlier. For any further queries, please open a support ticket in our dedicated support channel.

As Google has updated the API settings the error is coming. According to our investigation, it appears that if you are a Google WorkSpace user then you need to set the user type to internal.

Furthermore, if you are a free Google user, you must connect to the app in test mode as an external user. After connecting the app, you must publish it from testing so that your API key does not expire. We will update our documentation soon.

Thank you