Powerhouse, the UK's third biggest electrical retailer, has gone into administration, closing 50 stores and making about 500 staff redundant.
Powerhouse has been suffering in the cut-throat electricals market
The move came after PRG, its New Zealand-based owner, withdrew financial support for the loss-making chain.
PRG bought Powerhouse for £16m in 2003, after the then 223-strong chain entered administrative receivership.
Administrators BDO Stoy Hayward hope to sell the chain, based in Bicester, Oxfordshire, as a going concern.
History of losses
PRG said in May that it hoped to guide Powerhouse to break-even in 2006.
The retailer made a pre-tax loss of £1m in the last three months of 2005, and had been closing underperforming stores.
"Our members in Powerhouse have worked miracles in keeping Powerhouse afloat in the intensely competitive electrical goods sector," said Usdaw union general secretary John Hannett.
"They turned up for work today to be told the company has gone into administration and some have already been sent home, which is a devastating blow for them."
Administrator Martha Thompson said BDO Stoy Hayward had carried out a review of the Powerhouse business.
"It is with real regret that it has been necessary to close all the trading stores," she said. "We will continue to work hard to secure a sale of the business and its assets."
Customers who have made recent purchases and are worried about receiving them can call a helpline number - 0845 6034037.