Paypal Express Error: Security header is not valid

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    Asked on March 25, 2017 at 01:31 PM


    Can you please help me? I am currently integrating my client's paypal account to this form I'm making for her business. But unfortunately, when I'm testing the form... I'm getting an error. Please see screenshot below. 


    Not sure why. Please get back to me asap. Form link:

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    Answered on March 25, 2017 at 06:00 PM

    The security header is not valid error usually means that there is an issue with provided API credentials.

    Please re-check the PayPal API credentials on that form. Also, please note that PayPal API credentials for Live and Sandbox modes are different.

    If you need any further assistance on this, please let us know.