Gift vouchers for stricken electrical retailer Comet have been suspended, the chain's administrator says.
Deloitte, which was appointed on Friday, has launched an "urgent" search for a buyer to protect some 6,600 jobs at the 236-outlet chain.
But as a consequence, a Deloitte spokesman said: "Gift vouchers have been suspended temporarily while they assess the situation."
However, all Comet stores will remain open and the group's staff will continue to be paid in the meantime, according to Deloitte.
The collapse of Comet marks one of the biggest high street casualties since the demise of Woolworths in 2008 and comes a month after the failure of JJB Sports.
Neville Kahn, joint administrator and restructuring services partner at Deloitte, said on appointment: "Our immediate priorities are to stabilise the business, fully assess its financial position, and begin an urgent process to seek a suitable buyer which would also preserve jobs. In the meantime, all stores will continue to trade and all employees will continue to be paid. We appreciate the co-operation and support from the management, staff, customers, landlords and suppliers at what is clearly a very difficult time."
Deloitte said Comet had been hit by weak high street trading conditions, competition from online rivals and being unable to secure the trade credit insurance needed to safeguard suppliers.
"The inability to obtain supplier credit for the peak Christmas trading period means that the company had no realistic prospect of raising further capital to build up sufficient stock to allow it to continue trading," added Deloitte.
Angry customers took to Twitter to complain about not being able to use their Comet gift vouchers. Gavin McDonnell tweeted: "Voucher for #comet was good at 0900 this morning!", while Richard Alvin described his experience in a Comet store today. #comet experience went well this morning! No stock to buy, only selling contents of shop floor at normal price & won't accept £600 voucher."
Others, such as harvey @_harvo, ridiculed the company via the social networking website. "You're about as useless as a comet gift-voucher," Harvey tweeted. "How much would you offer for my £1 Comet gift voucher?" Dom Robinson tweeted.