Active PayPal Gateway Security Header Active Merchant Invalid

Question

I followed this railscast to set up an active trader on the rails 4.1 app.

While I try to create orders and pay, I get an error message from the PayPal server:

Security header is not valid 

My question is: what is wrong with my setup to have such an error?

By the way, does anyone know that I can fill in the cvv field for fake credit cards created using accounts in the sandbox.

Answer 1

The security header appears when:

• You are in real time, but you used the credentials (username, password and signature) from the test account or vice versa. Make sure that you are in test mode, you take the credentials from the sandbox account.

• If the credentials are really wrong. Make sure you don’t paste any space while copying and pasting credentials.

These are two possibilities for this error.

As for credit cards for the sandbox, yes, you can use any fake credit cards using any fake card generator.