completed the upgrade of its Web site on Monday - only for the site to go down for nearly an hour.
The technical glitch, which was unrelated to the launch, saw the site go down at about 10:30GMT for around 45 minutes.
Chief executive Brent Hoberman blamed the problem on a contractor developing online security for a South African venture and said he would seek compensation for loss of business.
As reported yesterday, the upgraded site, which was over four months behind schedule when finally completed, is based on a more powerful technology platform. This allows lastminute.com to focus more specifically at individual users, enabling it to promote more targeted offers. Customers can also design their own lastminute.com homepage through its MySpace service.
The technology platform is also designed to give the site greater power to integrate more languages and currencies.
Hoberman said the upgrade should help lastminute.com increase its conversion rates - the percentage of users who transact on the site. This year the rate of conversion was between five and seven per cent, he said.