What caused the global outage of Facebook, Instagram, and WhatsApp?

After a major outage on Monday affecting tens of millions of users around the world, Facebook, Instagram, WhatsApp, and Messenger are now officially back online.

All of the Facebook-owned platforms crashed early yesterday evening, meaning that users were blocked from accessing any of their services.

As well as being unable to access their social media accounts, iPhone and Android users reported not being able to make or receive phone or video calls or send messages. 

It has also been reported that Facebook’s internal systems, which are used by employees of the company, were down for a number of hours on Monday. 

Who was affected by the outage?

According to downdetector.com, the problems with Facebook’s apps were widespread, particularly in densely populated areas like Paris, London, and New York.  

The platform, which shows real-time status reports for various services, showed over 73,000 issues reported in the UK alone at 17.53 CET on Monday evening. There were also over 127,000 reports recorded in the US. 

The outages affected both website and app users, with many people being shown messages like  “This site is inaccessible” and “Impossible to find the server address”.

Some third-party apps that use Facebook credentials for a login were affected by the outage, too. This includes apps like Match Masters or Pokemon Go. 

What was the cause of the problem?

Although localized outages are fairly common, global outages are considered to be rare. Because of this, Facebook says it will investigate the cause of the problem. 

Content delivery company Fastly has blamed it on an undiscovered software bug. However, Facebook says, “the root cause of this outage was a faulty configuration change” and that there is “no evidence that user data was compromised as a result” of the outage.

The company has since apologized for any inconvenience caused by the outage and says it’s working to understand the underlying issues, adding there’s a high chance this was caused by human error or an “operational issue”.