Facebook says it has now repaired a widespread service outage Monday that prevented millions of users posting status updates, liking posts or submitting comments for more than four hours.
The error, which began just before 1pm GMT, prompted the warning message: "Couldn't Update Status. There was a problem updating your status. Please try again in a few minutes."
"Earlier this morning, while performing some network maintenance, we experienced an issue that prevented some users from posting to Facebook for a brief period of time," said a spokesperson.
"We resolved the issue quickly, and we are now back to 100%. We're sorry for any inconvenience we may have caused."
The issue had also affected payments on the site, as verified by alerts by Facebook's developer status. The problem effectively turned the site into 'read only' mode and was triggered by network maintenance.
Facebook has an estimated 700 million users daily. Its UK spokesman promptly tweeted that: "We're aware that some people are having trouble posting to Facebook at the moment and we're looking into it."
IT management firm Compuware, which has a dedicated tool for monitoring outage problems, said more than 3,500 third-party sites were being affected by the problems, which began at 12.50 GMT.
"This outage will have an enormous impact on millions," said Michael Allen, Compuware's director of advanced plant management, who had advised sites to check Facebnook's status before troubleshooting their internal systems
"At least 3,587 other domains were impacted although the actual number is likely to be far greater... many other businesses and websites are connected to Facebook through the integration of services from Facebook.
Outages on the major consumer websites have become more rare, but do still happen. Twitter's 'fail whale' was once a regular symbol of down time on the social network, but the service has become much more stable - despite a brief 40-minute error on the site in September.
Google's Gmail also suffered a 15-minute outage to its browser-based version in December 2012, and Spotify went down earlier this month.
• Radiohead's Thom York recently described Spotify as "the last desperate fart of a dying corpse"This article was written by Jemima Kiss, for theguardian.com on Monday 21st October 2013 16.41 Europe/London
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