Body: <p>I am using drupal 7.56 + civicrm 4.7.25
  I have a Paypal account and I configured a Payment Processor for test with the REST API credentials from <a href="https://developer.paypal.com" rel="nofollow noreferrer">https://developer.paypal.com</a></p>
  
  <p>REST API Sandbox account becomes PP User name
  REST API Secret becomes PP Password
  REST API Client ID becomes PP Signature</p>
  
  <p>This configuration does not work with error message :<br>
  Payment approval failed with message :Security error Security header is not valid</p>
  
  <p>Where can I find API credentials required by Payment Processor configuration ?
  And more generally could someone tell a detailed end to end Paypal Express Checkout Civicrm integration ? </p>
  
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2017-10-15T21:18:50.740Z
Comments.Text: Try using the "test mode" payment settings and method, see if that helps? Some CiviCRM payment processors *require* you to use "test mode" to access development environment (eg PayPal Sandbox vs PayPal Live), but behaviour varies between some CiviCRM payment processors. The CiviCRM Paypal docs are [here](https://docs.civicrm.org/sysadmin/en/latest/setup/payment-processors/paypal-standard/).
Comments.UserDisplayName: Chris Burgess
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2017-10-15T21:19:27.807Z
Comments.Text: Possibly answered over in https://civicrm.stackexchange.com/questions/3847/fixing-paypal-error-payment-processor-error-message-10002-security-error-secu?rq=1 ?
Comments.UserDisplayName: Chris Burgess
Tags: <payment-processor><paypal>
Title: Paypal Express API credentials
ThreadText: # Paypal Express API credentials
  
  (Asked by: username_0 on 2017-10-15)
  
  I am using drupal 7.56 + civicrm 4.7.25
  I have a Paypal account and I configured a Payment Processor for test with the REST API credentials from <https://developer.paypal.com>
  
  REST API Sandbox account becomes PP User name
  REST API Secret becomes PP Password
  REST API Client ID becomes PP Signature
  
  This configuration does not work with error message :  
  Payment approval failed with message :Security error Security header is not valid
  
  Where can I find API credentials required by Payment Processor configuration ?
  And more generally could someone tell a detailed end to end Paypal Express Checkout Civicrm integration ?
  
  **Tags:** payment-processor, paypal
  
  > **Comments:**
  > **username_1**: Try using the "test mode" payment settings and method, see if that helps? Some CiviCRM payment processors *require* you to use "test mode" to access development environment (eg PayPal Sandbox vs PayPal Live), but behaviour varies between some CiviCRM payment processors. The CiviCRM Paypal docs are [here](https://docs.civicrm.org/sysadmin/en/latest/setup/payment-processors/paypal-standard/).  
  > **username_1**: Possibly answered over in https://civicrm.stackexchange.com/questions/3847/fixing-paypal-error-payment-processor-error-message-10002-security-error-secu?rq=1 ?  
  
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  ## 0 answers
  
  