Microsoft is launching a Web-based service for organizing events and remembering them afterward – trying to move further into the highly competitive areas of social networking and online photo sharing.

The free Windows Live Events service, announced Thursday afternoon, will let people send online invitations that direct recipients to a related Web page, similar to IAC/InterActiveCorp.'s popular Evite.com site.

But Microsoft is putting a big emphasis on connecting attendees after the event takes place, letting them reminisce by posting photos, video and text about the event on the same page.

That's where the new service may face a challenge, analysts said, because of the multitude of social networking and photo sharing sites already in existence, from Facebook to Flickr.

"The issue is that everybody would like to be the page of record – the place where you go to do things, and as a result there are a lot of competing venues like that," said analyst Roger Kay, president of Endpoint Technologies Associates. "If you commit to one, in some sense you kind of decommit to the others. Either that, or you have no life."

Microsoft is also coming from behind. "A lot of this game is already established," Kay said.

At the same time, the notion of creating persistent event Web pages is interesting, said Kay, who had seen a preview of Windows Live Events. "Whether that becomes popular is something else, but at least its functionality is interesting," Kay said.

The service, at events.live.com, is expected roll out gradually over the next few days. It's part of a broader attempt by Microsoft to fill out its lineup of Windows Live online services.

Jay Fluegel, Windows Live Events product manager, said he doesn't think people will need to choose the service to the exclusion of other social-networking and photo sharing sites. For example, people will be able to embed photo albums from Windows Live Events into third-party sites, such as Facebook.

"Our goal with Windows Live is just to offer an integrated suite of services," he said. "In many cases, because of the number of Hotmail, Spaces and Messenger users we have, people have stored a lot of their contacts and relationships with us. That makes it easy when it comes to invitation scenarios and other entry points within Windows Live."

Microsoft will make money from the Windows Live Events site through an advertising banner at the top of Web pages.

The new service is based on the infrastructure for Microsoft's existing Windows Live Spaces blogging service, Fluegel said. As a result, Live Events won't be launching with the "beta" designation that normally indicates a service is new and glitchy. Fluegel said Microsoft is confident about the quality of the service.

Event organizers will need to have one of Microsoft's free Windows Live ID accounts, the successor to its Passport system. They will be able to enter e-mail addresses manually or use their existing contact list from other Windows Live services, such as Messenger and Hotmail.

People who receive invitations won't need a Windows Live ID to RSVP on the site and post a basic message about their plans to attend. But attendees will need a Windows Live ID to upload content about the event.

In addition to photos, people will be able to post videos on the site, after uploading them to a video site such as YouTube or Microsoft's Soapbox service.