The Connections tab is the one place your API keys live. Connect a service there and it appears in the autoresponder dropdown on every campaign you build afterwards.
Connecting a service:
- Open the Connections tab. Services are grouped by what they are, and the header shows how many of the 36 you have connected.
- Find your provider and fill in the credential fields it asks for. Every field has a Get your key link that goes straight to the right page on the provider's site, plus a How to find this in 60 seconds explainer.
- Click Connect.
Engage saves the credentials and then immediately tests them. If the test fails you get the provider's own reason back in plain English, and what you typed is kept so you can correct one field rather than retyping a long key.
Once connected, each card offers Test, Edit key and Disconnect. Test is a live round trip, so it is the fastest way to prove a key still works before you go hunting elsewhere.
AWeber is the exception:
AWeber finishes its setup with an authorize round trip rather than a pasted key. Its card shows the exact redirect URI to set on your AWeber app, then an Authorize with AWeber button that sends you to AWeber and back. Everything is verified on the way back, so a crafted link cannot connect somebody else's account.
Lists are cached for six hours:
Your lists, groups, forms or tags are fetched from the provider and cached, because the builder asks for them often and they change rarely. There is a Refresh button beside the list picker in the builder whenever you need a fresh copy.
Stored keys are never sent back to your browser in full. The Connections screen shows a masked value, and leaving a masked field untouched means keep what is already stored.
Already subscribed is treated as a success, not an error. A returning visitor who opts in again has done nothing wrong, and showing them a red failure message would be a bug from their point of view.