paypal错误 - 安全标头无效

Question

这就是我将paypal设置为自从我在这里下载脚本以来的方式。

http://www.sanwebe.com/2012/07/paypal-expresscheckout-with-php

我在这里设置了操作：http://www.sanwebe.com/2011/11/getting-paypal-api-username-and-password

我之前从未使用过此类作品，

它是错误的，它出现并说：

Error : Security header is not valid
        Array
    (
        [TIMESTAMP] => 2014%2d08%2d28T21%3a59%3a28Z
        [CORRELATIONID] => 8ffd52166445d
        [ACK] => Failure
        [VERSION] => 109%2e0
        [BUILD] => 12566246
        [L_ERRORCODE0] => 10002
        [L_SHORTMESSAGE0] => Security%20error
        [L_LONGMESSAGE0] => Security%20header%20is%20not%20valid
        [L_SEVERITYCODE0] => Error
    )