We are always glad to hear when WP Questions works out well for one of our customers. I just stumbled across this post on the forums for the WP eCommerce plugin:
pluggyboy: guys, not sure whether this will help anyone as my configuration was slightly different to that described above (using weight rate with no downloadable products) but I began getting the same error message at checkout.
With no answers here, I headed over to http://www.wpquestions.com and asked the question there, and for $35 got the answer within a few hours, which is available here: http://www.wpquestions.com/question/show/id/144
hope this helps someone, thoroughly recommend the site if you’ve a plugin / theme issue you cant get resolved by the owner, there’s a great community of very skilled people over there who are willing to help for relatively small micro payments.
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