WhatsApp, Facebook and Instagram saw global outage affecting over 10m people which wiped out billions from its share value.
Shares closed at 4.9% lower on Monday which wiped off £34.5bn off its market value as 10.6m people were unable to access any of the services.
Facebook blame a “faulty configuration change” and has proven how much the company is now part “of the critical infrastructure” in the US and around the world.
Facebook said, “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.
“We’ve been working as hard as we can to restore access, and our systems are now back up and running.
“The underlying cause of this outage also impacted many of the internal tools and systems we use in our day-to-day operations, complicating our attempts to quickly diagnose and resolve the problem.
“Our engineering teams have learned that configuration changes on the backbone routers that coordinate network traffic between our data centres caused issues that interrupted this communication.
“This disruption to network traffic had a cascading effect on the way our data centres communicate, bringing our services to a halt.
“Our services are now back online and we’re actively working to fully return them to regular operations.
“We want to make clear at this time we believe the root cause of this outage was a faulty configuration change.
“We also have no evidence that user data was compromised as a result of this downtime.”