HTTP codes you will most often see
The connector contract is intentionally small, so the same HTTP codes appear again and again. Read the code first, then read the JSON body, because the code tells you whether the failure happened before authentication, after authentication, or during unexpected server processing.
- `200 OK` means the request succeeded and the returned JSON shape was accepted.
- `401 Unauthorized` means the bearer token was missing, wrong, or stale. This is the first error to expect after API key rotation.
- `403 Forbidden` on repo UI endpoints usually means the plan or page context does not allow the action. It is not the normal code for the partner bearer endpoint.
- `405 Method not allowed` means the endpoint did not respect the POST-only contract.
- `419 Invalid request` is specific to internal signed-in repo UI endpoints when the browser session or CSRF token is stale.
- `422 Unprocessable entity` means the request was authenticated but the payload was invalid, such as missing email, missing access token, invalid JSON, invalid CSV, or no valid emails.
- `500 Internal server error` means an unexpected server failure on whichever side received the call.
- An invalid partner JSON body is often surfaced as an invalid response message inside ProLogbooks, even when the raw HTTP status from the partner looked successful.
Repo messages on the ProLogbooks side
Some failures appear as ProLogbooks messages instead of raw server logs. Those messages usually point directly at the missing configuration or the missing connector-user mapping.
- `No connector access token was found for this email address.` means the user email is not present on the Connector users page for this connector, or the row was removed.
- `This connector does not provide a check endpoint.` means the check URL was not saved on the partner connector card.
- `This connector does not provide a preview endpoint.` means the preview URL was not saved on the partner connector card.
- `The connector flight sync endpoint returned an invalid response.` means the partner JSON was malformed or did not match the accepted object or array shape.
- `No partner connector was found for this account.` means the account owner has not saved the partner connector card yet.
- `Upgrade your account plan to activate a partner connector.` means the current account plan does not include the feature.
User statuses on the Connector users page
Some warnings are not HTTP errors at all. They are account-state clues shown in the UI so you know whether the person can actually use the connector yet.
Typical JSON error body
{
"error": "User is not allowed to fetch flights."
}- `Not created` means the email is allowed for the connector but no ProLogbooks account exists yet.
- `Pending` means the account exists but email verification is not finished.
- `Active` means the email exists and is verified, so normal connector checks can proceed if your server also recognizes the email and token.
If something goes wrong
- If you cannot tell which side failed, test the partner endpoint manually with the same bearer token and payload first.
- If manual tests pass but the UI still fails, compare the exact email address and access token stored on both sides.
- If failures started after changing endpoint URLs or regenerating keys, assume a stale configuration mismatch before suspecting the flight data itself.