E-commerce site eBay crashed over the weekend, causing its search function to stop working.
The site was back up by Monday, after the technical problems led to searches returning limited or no results throughout the day on Saturday.
EBay said the problems were "unanticipated" and the result of a surge in live listings as sellers place more items on the site in the run-up to Christmas.
The company says it currently has more than 200 million live listings, a third more than at this time last year.
The company said, "The technical issue, once identified, was easily fixed and was implemented across the site's servers throughout Saturday afternoon and evening."
Increasing numbers of users are turning to online retailers as website usability improves and the number of big brands online continues to grow. This Christmas is expected to be the most successful yet for online retailers.