If he filed his self-assessment returns up to and including the year of cessation in 2008 then any over or under payments would have been dealt with on them ( assuming everything was returned correctly). However as DB74 said, more information is really needed.
If he was a sole trader he may be entitled to claim termination relief. If he paid income tax in the three tax years before year he ceased trading he can set off any loss made in final year against those previous three years.
If he traded through a company this can also be claimed but only against the corporation tax of the company.