Authorization Error – Invalid_client The OAuth client was not found

SupportAuthorization Error – Invalid_client The OAuth client was not found
Gabriela LeBaron asked 4 years ago
Hi, I saw that someone else had this exact problem but there were no answers to resolve the issue so I am posting the question again. Life the other person, I also follows the steps to the dot and when I click Authorize I just get a popup that says "Authorization Error" Error 401: invalid_client The OAuth client was not found.  Thank you for your help with this! I am not sure what else I should do. 
1 Answers
Nikola Loncar Staff answered 4 years ago
Hi Gabriela can you please check Google Console settings and see if Client id is fine? Best regards Nikola
gabriela_lebaron Staff replied 4 years ago

Hi Nikola, I did that and realized that now a new message pops up. It says “This app isn’t verified”. Then it says “This app hasn’t been verified by Google yet. Only proceed if you know and trust the developer”.
“If you are the developer, submit a verification request to remove this screen. The a link that says “Learn More”. Then there’s a complicated page about unverified apps.

When I was filling out the OAuth form, it asked if it was for Internal or External users. There was only one option because I don’t have a G-Suite account, so it could only be External. And since it’s external, it says it has to go through this verification process. I submitted the verification form already and got another message that it would take 4-6 weeks.

Last night I got an email from them saying that they’ve looked at my verification request and believe that I need it for Internal use. This being the case, I need to go to my OAuth screen and click “Make Internal”. Well, once I get there, I can’t make it internal without having a G-Suite account. So now we are going in circles.

Oh, it also says that I have to “associate my project with my organization” and I have to “create an organization”… then there are some steps it tells me about.

Please advise! Thanks 🙂

By the way, I don’t know if what I am using the Appointment app for is Internal or External. I researched that a bit and didn’t find a clear answer.

Nikola Loncar Staff replied 4 years ago

You don’t need to verify app just when you see that warning go to Proceed at the bottom and finish that wizard 🙂

Best regards,
Nikola

gabriela_lebaron Staff replied 4 years ago

Hi Nikola, I had tried to proceed but it was not letting me. It turns out, you have to click on the tiny ‘Advanced’ button, then at the bottom you will see a small line that says ‘Return to_your domain’ in my case, it’s R2Society with (unsafe) in parentheses. Just click on the return and it will take you to the window where you can allow the app permission to add to your calendar. It’s hidden, but it I finally made it!