Open the Email Opt-in module Settings modal window

Go to the Content Tab → Email Account

Select the AWeber from the provider's list.

You will be redirected to AWeber website to grant access

Fill in the login information.

Click on the Allow Access button

Copy the Access Key that Aweber creates for you.

Type a name for your account - it can be anything you want.

Paste that Key into Email Opt-in module's Authorization Code field

Click on the Submit button.

Choose the AWeber List that you want to use.