Random 401 errors

Campaign Contributor



We've been building a Constant Contact integration, and we've been experiencing a problem where seemingly at random, an access token that worked previously, and was refreshed in the last hour starts returning 401 response codes.


I found this post, https://community.constantcontact.com/t5/Authentication-and-Access-ie-401/Random-401-unauthorized/td... , which implies that when going over the rate limit we'll receive 401 responses. However the official docs say that we'll receive 429 responses in that case. https://v3.developer.constantcontact.com/api_guide/rate_limits.html  Could you please clarify what behavior we should expect, and maybe update the docs if they're not correct? This has been impacting our customers and forcing them to go through the OAuth flow repeatedly. We're frustrated here with the inconsistent behavior and incorrect documentation.

0 Votes

Hello @AdamM5071,


Thank you for reaching out to Constant Contact's API Support.


The post you referenced is for our v2 API and can be verified by looking at the tags to the right of the post. You linked to our v3 API documentation which uses a different error codes.


If you go over your rate limits when using the v3 API you should be getting a 429 error. If you are getting a 401 error it is for a different reason most likely related the Access Token expiring.



Jimmy D.

Tier II API Support Engineer

Jimmy D.
Tier II API Support Engineer
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