Mozilla's plan to set a world record for downloads came gloriously unstuck when its website failed to work properly. The company had hoped that downloads for its Firefox 3 browser would shatter all records but sporadic problems with the US site meant that many frustrated would-be users were not able to access the site.

A spokeswoman said that the company was aware of the problem and "working to get it back up quickly." The company also outlined the problems it was having with its website in a Mozilla blog entry.

"The outpouring of interest and enthusiasm around Firefox 3 has been overwhelming (literally!)," according to the post. "Our servers are currently feeling the burn and should be back to normal shortly."

European users fared better: the European site for downloading Firefox 3, which kicked off the 24-hour record-setting process, was up and running in the evening said the company.

In a blog entry soon after the US site went up, the company said it was logging about 14,000 downloads a minute.

"This will put us well into the tens of millions of downloads in a 24 hour period if we can sustain it," according to the post.

Mozilla unveiled a campaign on 28 May to set a Guinness World Record for the most software downloads in 24 hours with its Firefox 3 browser. There is no world record for software downloads; Mozilla is trying to create one.