invalid_client in google oauth2

Set/change your product name, I had this issue until I created a product name as same as project name.

The product name can be set in the Consent screen section of the Google Developers Console for your project. Look under APIs & auth in the left navigation and select Consent screen. You need also to set your email address in the box above the product name.

After copy values from Google web UI, I had a blank space for:

• client_id
• secret

And at the BEGINNING and at the END for both.

This happens even when clicking on the "copy" button.

Trim the leading and trailing white space from both the client_id and client_secret. Google's copy button does not do this for you.

Set both the email address and product name fields for the OAuth consent screen.

Setting EMAIL ADDRESS and PRODUCT NAME in the consent screen of Google developer console, solves the error "Error: invalid_client. The OAuth client was not found." for me.

I had .apps.googleusercontent.com twice in my ID.

It was a copy and paste issue "Your ID HERE".apps.googleusercontent.com