title: Paypal Express Checkout : 10410 Invalid Token
body: <p>I Am using the Paypal Express Checkout API on my web site, and encountering an error while on the sandbox site. The USER, PWD and SIGNATURE fields have been verified and are correct. I have replaced ampersands with newlines for readability.</p>
  
  <p>First, my SetExpressCheckout request: </p>
  
  <pre><code>USER=xxx
  PWD=xxx
  SIGNATURE=xxx
  VERSION=76.0
  METHOD=SetExpressCheckout  
  RETURNURL=xxx
  CANCELURL=xxx
  REQCONFIRMSHIPPING=0
  NOSHIPPING=1
  LOCALECODE=FR
  SOLUTIONTYPE=Sole
  LANDINGPAGE=Billing
  PAYMENTREQUEST_0_AMT=86.11
  PAYMENTREQUEST_0_CURRENCYCODE=EUR
  PAYMENTREQUEST_0_ITEMAMT=72.00
  PAYMENTREQUEST_0_TAXAMT=14.11
  PAYMENTREQUEST_0_INVNUM=1tyZq03X5c8
  PAYMENTREQUEST_0_PAYMENTACTION=Sale
  PAYMENTREQUEST_0_PAYMENTREQUESTID=1tyZx03f5c8
  </code></pre>
  
  <p>The response from Paypal is as follows:</p>
  
  <pre><code>TOKEN=EC%2d9FE8384171515313J
  TIMESTAMP=2011%2d08%2d24T08%3a44%3a36Z
  CORRELATIONID=696e70dbd6086
  ACK=Success
  VERSION=76%2e0
  BUILD=2055089
  </code></pre>
  
  <p>After the user fills in the payment for on the Paypal site and returns to the confirm URL specified above, I run the GetExpressCheckoutDetails:</p>
  
  <pre><code>USER=xxx
  PWD=xxx
  SIGNATURE=xxx
  VERSION=76.0
  METHOD=GetExpressCheckoutDetails
  TOKEN=EC-9FE8384171515313J
  </code></pre>
  
  <p>The response is:</p>
  
  <pre><code>TIMESTAMP=2011%2d08%2d24T08%3a45%3a56Z
  CORRELATIONID=6a2bbe8363462
  ACK=Failure
  VERSION=76%2e0
  BUILD=2055089
  L_ERRORCODE0=10410
  L_SHORTMESSAGE0=Invalid%20token
  L_LONGMESSAGE0=Invalid%20token%2e
  L_SEVERITYCODE0=Error
  </code></pre>
  
  <p>The code that provides the token has not changed for a month (and it worked correctly until several minutes ago). Judging from the logs, there was no change in the structure of my requests, so I am assuming this must be a configuration problem on the PayPal side.</p>
  
  <p>A detail which might be of importance: I reset the seller account in the sandbox before the system started to malfunction, but I made sure that the API credentials are the correct ones (they did not change when I reset the seller account).</p>
  
  <p>Any ideas why I am getting this error all of a sudden?</p>