Newlands School, in Seaford, East Sussex, has told parents it has been forced to close immediately.
Its landlords refused to allow Cognita to take over its lease.
The school is believed to have incurred debts after if bought a house for its boarders. It declared itself bankrupt when it became clear the trustees and owners of the land and most of the buildings would not reassign the lease.
References: The Times 05/04/06 page 8, The Daily Telegraph 05/04/06 page 4