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Account Authentication failed for C#

Occasional Contributor

Account Authentication failed for C#

I am doing the following but I keep getting Account Authentication failed.

I just place xxxx's in as placeholders but I put in the real data in my code.

Is there something you have to do on your end to enable me.




string _apiKey = "xxxxxx";

string _userName = "xxxxxx";

string _password = "xxxx";


AuthenticationData authdata = new AuthenticationData( _apiKey, _userName, _password );


Utility.IsValidUserAuthentication( authdata );

Honored Contributor

Re: Account Authentication failed for C#

Hello Stacy,


I have done some investigating to see if your application was able to connect to Constant Contact correctly and I did find that your requests were being sent successfully and being denied because of incorrect login credentials.  You will want to make doubly sure that API key and password are both typed correctly. The specific error that was coming back to you is a HTTP 401 error which is what is returned when the UN/Pass do not match your Constant Contact account.


If you are still having difficulty after verifying that your login information and API key are correct, I would suggest contacting us at so that we can investigate your code in more detail without making those details public.



Elijah G.

Tier 2 Support

Elijah G.
API Support Engineer
Occasional Contributor

Re: Account Authentication failed for C#

Thanks I will email them the issue.

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