SEATTLE – Microsoft Corp.'s new digital photo sharing site spent most of its first day offline as its servers strained to handle a flood of traffic.

The site, called Photosynth, stitches together a set of related digital photos into a presentation that allows viewers to zoom and pan across the scene.

Microsoft employees and partners including National Geographic had been tinkering with a private beta version of the technology. Microsoft was set to open Photosynth to the public late Wednesday, but on Thursday morning the working site had already been replaced by a page that displayed an apology.

On the Photosynth blog, a team member wrote that engineers were “hard at work adding capacity and getting the full site back online.” At 1:50 p.m. Pacific, the blogger added that the site would be back up “shortly.”

During a preview of the final product on Tuesday, David Gedye, a group manager for Microsoft's Live Labs, said the team had been beating on the site to simulate the rush of new users expected after launch. But when asked, he sounded less than confident that the technology could withstand the pressure.

“We're very nervous,” he said during an interview.

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