paypal express checkout =>Error: Security header is not valid

Question

Error : Security header is not valid Array

(
    [TIMESTAMP] => 2014%2d04%2d29T07%3a24%3a29Z
    [CORRELATIONID] => 6af6749c848d6
    [ACK] => Failu         


        

Answer 1

generally this error means you are not using the correct API credentials. If you are convinced your credentials are correct then take a look at your endpoint. Sandbox credentials will not be valid in the production environment and live credentials will produce this error in the sandbox