Kingfisher mistakenly circulated some draft figures on Monday afternoon, forcing the DIY retailer to admit that adjusted pre-tax profit for the six months to 1 August will be between £285m and £290m, much better than expected.The B&Q owner, which hadn't been due to report its interims until 17 September, blamed an administrative error for the early external release of the results.Kingfisher shares build gains as analysts had only been forecasting a profit of about £268m.Retail profit will be in the range of £345m-£350m, broadly made up of £148m in the UK and Ireland, £146 for France and £53m in other international markets. Kingfisher stressed that these figures are yet to be approved by its Audit Committee and the board, so could be subject to change.The rest of the results will be announced, as planned, on the 17th when the firm promises to outline plans for the rest of the year, 'in what is expected to be a challenging trading environment'.