Sign-up error

0 Votes

On my websites and my sign-ups are not working. I get the error "API call failed. Server returned status code 400" Apparently this started a couple of weeks ago and I didn't realize. I've not been able to get new sign-ups since January 20. I need to get this fixed right away but have no idea where to start. Thanks.

0 Votes

Hello RondallR ,


Thank you for reaching out to Constant Contact API Developer Support. My team is here to assist outside software developers with questions about building into Constant Contact's API.


Based on our logs for your form, it looks like the key is connected and making GET calls successfully, so the error appears to be isolated to the POST calls to create new contacts. Response code 400: Bad Request indicates that either the JSON request body  was malformed or does not conform to the expected schema and that there was a data validation error.


It looks like you may have already started resolving the issue, as I do see a successful POST request today. However, if you have any follow-up questions or want us to take a look at some of the request bodies from previous failed calls, please feel free to email those logs to our team at and we’d be happy to take a look.


Courtney E.
Tier II API Support Engineer

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