Many Facebook users worldwide were unable to access the Social Networking Site for several hours on Tuesday. There were also reports that the site was even showing that the domain is not even registered this landed in many Domain Name selling Websites get queries on buying the domain Name www.facebook.com. Facebook said in a statement that the issue was not region specific and was caused by a bug in some domain name system (DNS) optimization work undertaken at Facebook earlier in the day. “Earlier today, we experienced a DNS issue that briefly prevented people who typed facebook.com into their browsers from reaching the website. People who accessed the site using a mobile application, typed www.facebook.com into their browsers, or used a bookmark or a search engine to navigate to the site were not affected,” the company said that in a statement. Users of the site faced similar problems that Facebook attributed to DNS issues in June and December 2012. “We resolved the issue quickly, and the fix should be fully propagated by now. We apologize for any inconvenience caused,” Facebook added.