This is a known intermittent issue which has to do with our payment processor, 2Checkout. Since we had a lot of clients ask us the same question we asked them to explain us what that error code means. This is the reply that a 2Checkout Integrations Agent named Daclaud gave us through their support system on December 19th, 2012:
"" We apologize for any inconvenience this may have caused, but the PE 101 Error message just indicates that an incorrect (or no SID number) was passed in to the 2Checkout cart system. Since Pay Pal redirects to paypal.com, the reason why your customers may be experiencing this issue with is because they may be pressing either the back button or the forward button (depending on which screen they were last on) causing them to enter the purchase page of 2checkout.com with an empty cart with no parameters being passed, which will result in the PE 101 Error.
Other than that, orders are able to be processed just fine. ""
According to our experience, this happens with almost every subscription paid with PayPal on certain periods of time that are outside our control. 2Checkout is unable to track down the issue. However, your subscription should be properly created and there is really no problem. The only issue is that this message is shown in error and confuses our clients. We apologise for the inconvenience and we'll keep on pursuing a solution with 2Checkout.
Please note that if your subscription has NOT been created (please check the My Subscriptions page on our site) you can always use PayPal directly to make a payment, without going through 2Checkout. In the subscription page of our site please use the PayPal option instead of the 2Checkout one. Alternatively try clearing your browser's cookies (at the very least any cookies originating from paypal.com) and retry. This usually fixes the session issue with PayPal.
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
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