Facebook users around the world were in distress as many issues with logging into and posting on the site were reported throughout the day Wednesday. The outages lasted nearly a full day, making it Facebook’s longest downtime ever. Instagram and WhatsApp were also down throughout the day.

In a statement released Thursday, Facebook blamed a “server configuration change that triggered a cascading series of issues” for the outages. The company later stated that its services were coming back online.

“Yesterday, we made a server configuration change that triggered a cascading series of issues,” said a Facebook spokesperson. “As a result, many people had difficulty accessing our apps and services. We have resolved the issues, and our systems have been recovering over the last few hours. We are very sorry for the inconvenience and we appreciate everyone’s patience.”

Facebook acknowledged the outage previously via a tweet Wednesday, saying, “We’re aware that some people are currently having trouble accessing the Facebook family of apps. We’re working to resolve the issue as soon as possible.”

It later confirmed that a DDoS attack, which refers to a Distributed Denial-of-Service attack in which “a hacker overwhelms a site by flooding it with fake traffic,” as CNBC reports, was not the result of the problem.

“We’re focused on working to resolve the issue as soon as possible, but can confirm that the issue is not related to a DDoS attack,” tweets Facebook.

While Facebook shares were relatively unchanged Wednesday afternoon, it took a 1.8 percent decline Thursday morning.

According to Downdetector, a website where users can report problems on apps and websites, reports of problems peaked over 12,000 worldwide as of late Wednesday.  It cited over 300 reports on Thursday morning, though many reported that their access had been restored.

Users reported that they were unable to load the site and unable to post comments. Users took to Twitter to post screenshots of error messages when they tried to load the Facebook app. Some users’ were receiving a message saying “Account Temporarily Unavailable.”