Recently I stumbled upon an error while trying to pass a shopping cart to the payment provider Google Checkout.

The error was:

“Error parsing XML; message from parser is: The entity “Acirc” was referenced, but not declared.”

After hunting around and a bit of searching on the net, the issued stemmed from having a `£` in a product’s option name. Removing the `£` sign seemed to fix the issue. So if you ever run into this issue it would be wise to check if there are any £ signs in your xml.

Strange error so I thought I would note it here for future ref and others to see.