PayPal gateway has rejected request. Security header is not valid (#10002: Security error Magento

Question

up the pay-pal advance in magento . I have fill all the credentials in magento admin . BUt when i go to frontend and click pay-pal button it gives

Pa

Answer 1

This error simply means your credentials are wrong. Please check with the credentials. If you are using sandbox then you are supposed to provide facilitator related credentials.