Now I have a voice in my head saying "you were sooo stupid to buy this HP calculator"

[Derek W]

(08-01-2015 05:44 PM)Sukiari Wrote:  [Actually I think you can make your claim to the UK's consumer agency and they will help you. I do not believe you have to contact HP at all except to claim your refund.

Generally UK consumer legislation gives the buyer redress against the retailer (and it is then up to them to claim their loss back from the manufacturer). Since the OP apparently bought the calculator from China, the retailer may not be covered by UK law, and/or may choose to disregard it.

Local authority Trading Standards departments (who enforce the legislation) have been much cut back, are short of staff, and are unlikely to comprehend a 'not fit for purpose' argument based on software bugs, particularly if they are in uncommon functions. Unless the calculator won't turn on, or gets incorrect answers to simple arithmetic, I wouldn't expect much help.