404 error not found on checkout
We've had some cases where customers stepped through the checkout wizard and confirmed the order only to get a 404 error when the site tries to hand off to PayPal. 404 errors mean the exact location on the web you asked to see was not available. Several problems can cause this, the easiest one to resolve being a loss of Internet connection.
Unfortuneately it's very difficult to pin down the exact cause in each case, The evidence we have been able to collect from some of our customers points to a security option on the customer's device that is blocking the feature used by our site to pass your browser over to the PayPal site to complete the transaction. This appears more often on customers using macs and I-pads or using Safari or Chrome as their browser, however others using these same devices have successfully checked out. This points to optional individual device settings as the cause--most likely in overly aggressive security settings such as a firewall or even workplace network settings that block access to PayPal so workers don't shop on company time!