How to Obtain Google API Client ID and Secret

In order to connect to the gmail smtp server with a more secure connection, a client ID and secret is needed to authorize the specific app. These will be obtained from within the google account settings page. Therefore, access to the google account username/password is required for these steps. These steps can be done without cost this way because there's no need for a Google Organization or Workspace to be created.

Create a new API Project

1	Open the Google API Console. It should look something like this.
2	Click "CREATE PROJECT" on the far right.
3	Choose a Project name like "Gmail SMTP" or similar, then click "Create"
4	Once the project is finished creating, click "ENABLE APIS AND SERVICES" on the main dashboard(:
5	Search for and Select the Gmail API
6	Click Enable.

Set API Scopes/Users


1	On the left sidebar, click "OAuth consent screen". Choose "External", then click the Create button.
2	Enter information for your app. This will appear when logging in and asking for permissions. An app name like "Gmail SMTP" works here.
3	Click "ADD OR REMOVE SCOPES"
4	Filter on "mail.google.com", click the checkbox next to that result. Then click "Update" at the bottom of the screen(may need to scroll down to see it).
5	At the bottom of the screen there should now be an entry in the "Your Restricted Scopes" table. Click "SAVE AND CONTINUE"
6	Click "+ ADD USERS". Add the email addresses of anyone that may use or request permissions from this API/app. When all are added, click "SAVE AND CONTINUE"

Create Credentials

1	Click "Credentials" on the left sidebar, then the "+ CREATE CREDENTIALS" at the top.
2	Choose "OAuth client ID"
3	Choose "Desktop app" for Application type and name the app something similar to "Gmail Client". Then click Create.
4	When the credentials are shown, copy the Client ID and Secret. These are the credentials that will be used when setting up the mail sender client. Or download the json which contains all the info as well.
5	These credentials can then be found on the dashboard if they need to be edited or viewed later.

This entire process can be repeated multiple times if needed, however there is a limit to the number or projects and users that can be added.