I have a bit of a problem and was wondering whether I could hire your help to solve the problem.
My magento site went live a couple of days ago and we have stumbled on an issue... when people checkout 'as a guest' all is fine.... but when they create and account and login and then try to order you get an error and get taken back to the shopping cart again. I can replicate the error and have screenshots of the error number. This procedure continues over and over until they get fed up with trying.
Is this a job you would be interested in taking on?