LONDON (ShareCast) - Shares in Z Group plunged after the marketing technology services firm warned full-year results will be adversely affected by the lower than expected take-up of its file sharing platform OnShare.

“Management expectations for trading for the full year to 28 February 2008 include a substantial contribution from the company's investment in OnShare,” said the group.

“At the present time the board is not confident that those expectations will be fulfilled as take-up of the product by consumers has been lower than anticipated,” it added.

Z Group said it expects to write off its investment in this product and is looking at alternative ways to generate revenue from the underlying OnShare technology.

The monthly average cash burn in the first half was around £115,000 on a cash balance of £1.6m at 31 August.

The group added that trading for the first half of the financial year was better than budget, thanks to the performance of its Internet acceleration software OnSpeed.

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