The social media site, alongside Instagram and Messenger, were unavailable for users last Monday.

Facebook. A company that has become ingrained in daily life for billions of users around the world, is a company that has seen much swift growth in the past while seeing much slower growth recently.

This past Monday, despite being one of the largest companies in the world, Facebook experienced an unusual shutdown. Messages stopped being sent. Photos stopped being synced. Posts stopped being shared. Normal life for many around the world ceased.

It was around 10:30 a.m. on Monday morning when business around the world halted as the Facebook products went dark. Facebook, Messenger, Instagram, WhatsApp and Oculus all stopped working as the entire Facebook network seemed to be down. People began to wonder what caused this outage. Was it an attack on Facebook? Was it a configuration setting that Facebook got wrong in their network configuration? These were all questions being asked as people pondered what was causing this outage.

This outage came as Facebook has come under intense scrutiny for how its reach has an impact on society. Recently, the Wall Street Journal has published an article series entitled “The Facebook Files” that details how Facebook knows the ill effects its platform can have on its users but has not done what it should have done to fix this. Also last Monday, there was a hearing in Congress where Facebook whistleblower Francis Haugen testified on how Facebook’s products have been harming its users.

About forty-five minutes after the outage began, WhatsApp was the first of the products to notify its users through a Tweet that they knew about the issues and were working to fix them. About ten minutes later Facebook notified its users that they were working on a fix to the issue and Instagram said a similar thing a few minutes after that.

The outage did not just affect the products that the end users use, but it also affected the internal systems that Facebook uses to communicate among the employees. Internal email, work passes, and the system that Facebook could have used to remotely fix the problem all ceased working during this outage. As a result, Facebook employees had to travel to the physical data centers to reset the systems that were causing the outage in an attempt to solve the issue.

While this outage caused major issues for people around the entire world, it was resolved about six hours after it began. At 5:33 p.m., Facebook apologized for the outage and posted a statement regarding the cause of the outage. “To all the people and businesses around the world who depend on us, we are sorry for the inconvenience caused by today’s outage across our platforms… Our engineering teams have learned that configuration changes on the backbone routers that coordinate network traffic between our data centers caused issues that interrupted this communication. This disruption to network traffic had a cascading effect on the way our data centers communicate, bringing our services to a halt.” The problem was fixed and Facebook ensured that this issue will not occur again.