Error: Security header is not valid

When i activate PayPal account and want to pay online i get the following error: Security header is not valid

This was not in version 1.3.3

I can agree, have the same problem here. ( Test Mode )

Info: I am using normal mode btw.

As far as I know there wasn’t anything changed in the PayPal handling… :worried:

Found this:
A problem related to the PayPal accounts.

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I know for sure that i typed/copied the correct information. I did it 3 times with no luck. So i deleted the API key and requested another one. That fixed it for me.

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Security header is not valid       

Error appears only if I am in test-mode. “Live” works or at least redirects to paypal and showing correct totals and invoice number.

In my case this was caused by spaces at the beginning/end of the paypal username/password/signature from when I copy pasted the info over.

This is a very helpful information! I will check this.

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