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API Problem: 500 Internal Server Error & ServiceOperationIdentificationFailure

New Member

API Problem: 500 Internal Server Error & ServiceOperationIdentificationFailure

Our application has been integrated with Constant Contact for a couple of years now, and we just started having an issue with our API calls.  About a week ago, we started receiving 500 Internal Server Error for every call our system makes, and we receive the following in the response body:

Fault Name: ServiceOperationIdentificationFailure

Error Type: Default

Description: Service Operation Identification Failure

Service: LoadBalancer_HTTP_Check

Endpoint: loadbalancer_client

Operation (Client):

Is anybody else having this issue?  Does anybody have any suggestions for resolving the problem?



New Member

I should also mention that I

I should also mention that I can't seem to find any documentation to support the version of the Constant Contact API we are using. 

This is the URI that we are currently posting to:


New Member

having the same issue

I've been having the same exact issue for the past week and it's been a pain to solve. The only difference being that i'm using php cURL and using a different uri to post:

Is anyone else having the same issue or have any recommendations on how to fix?




Hi JD, The problem you are

Hi JD,

The problem you are facing may be related to what the first poster is seeing.  However, we have not seen the error message you are refering to with our Contacts REST API.  We would need to see some more information to troubleshoot this further.  If you could email our webservices support team with the following information, we will look into it on our end:


Code used to generate the request

XML sent causing the error message

RE: Connection Power:  I will be sending you an email to set up some time to talk about the problem you are facing.  There is a specific issue we need to address and it is best to do this one on one.

Dave Berard
Senior Product Manager, Constant Contact
New Member

 I've sent a message to the

 I've sent a message to the webservices team prior to my post. I'm just waiting for a reply. 




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