A "major" Xbox outage beginning Sunday night left millions of players unable to access purchased games, sign in to their accounts, or use the Xbox Store for roughly 15 hours before services were restored.

Microsoft on Tuesday revealed the outage was triggered by a failure in a shared licensing service.

In a lengthy post on X Tuesday, Xbox CTO Scott Van Vliet called the outage "an unacceptable situation."

"This caused some sign-in scenarios to fail, and it caused many scenarios that require an entitlement check to also fail, such as listing out your Full Library and launching games that you own,"

Van Vliet wrote.

Van Vliet also said the failure affected “several of our publishing and store partners who depend on those same systems, which is why some of you saw issues in specific games and not others."

The CTO Van Vliet vowed the company would conduct "a full post-incident review" to understand why a single service failure caused such widespread disruption, why recovery took so long, and how to prevent it from happening again.

Players lose access to purchased games

The widespread outage first hit players Sunday at 11:10 p.m. Eastern Time, according to the official Xbox status page.

“We are aware that some users are encountering errors when attempting to sign in, see your game library, or launch games. Our engineers are actively working to mitigate the issue,” the gaming giant posted on X early Monday morning – nearly 12 hours after the disruption began.

Xbox said that users may have issues signing in to their Xbox profiles, be randomly disconnected from their accounts while signed in, or experience other related problems.

“Features that require sign-in like most games, apps and social activity won't be available,” it said.

Xbox lists the outage as affecting multiple services, including:

• Accounts & profile
• Store & subscriptions
• Games & gaming
• Apps & mobile

Additionally, many users have lost access to their own purchased games, are not able to play disc-based games, and can’t see games in the Xbox Store, the update said.

Xbox platforms impacted by the outage include:

• Xbox Series S|X
• Xbox One Consoles
• Xbox 360
• Backward compatibility

Xbox outage drags on for 15 hours

Internet outage monitoring site Downdetector showed a peak of 3,339 user reports in the US, before dropping dramatically around 6:00 a.m. – presumably while most people were asleep – and then rising again to quadruple digits by around 1:00 p.m. Monday afternoon.

Of those reports, 66% of users said they had problems launching games, 13% had issues playing games, and another 12% reported server connection issues.

In an update at 1:28 p.m. on Monday, Microsoft posted that it had identified the issue and listed resolution as “pending.”

But barely an hour later, the company followed with another update, stating that the fix was “taking longer than anticipated.”

At 8:15 p.m. ET, Microsoft announced the Xbox outage had been resolved and that players could once again launch games, sign in, and complete purchases.

“Thanks for sticking with us through a long one,” the company said, urging players to report any remaining problems.

Players vent frustration

As the outage dragged into its second day, frustrated players flooded social media to report being locked out of games they had already purchased.

And while some users began reporting services coming back online by the afternoon, many more continued their tirade, condemning the service for sign-in failures and inaccessible game libraries.

"Absolutely pathetic. We pay for Xbox, Game Pass, and games we can't even access because of your outages. Stop hiding behind generic status updates and fix your broken service. Customers deserve better," one user replied to Xbox Support on X.

On DownDetector, another player wrote: "I was just playing last night and now wake up this morning to not being able to play anything and no time line on when it will be fixed or worked out."

And while some users began to report services beginning to come back online by the afternoon, more continued reporting sign-in failures and inaccessible game libraries.

Users claim licensing glitch

Separately, some Xbox users claimed the outage may have triggered unusual licensing behavior.

One X account dedicated to “sharing Xbox leaks, news, and trivia” said the Xbox community had “found a possible exploit” related to the Xbox outage, sharing two screenshots showing the behavior.

“According to several users, it's possible to download from the Xbox app some games that no longer appear available in the Microsoft Store and even launch them as if the license were active,” the X user wrote in Spanish.

Cybernews reached out to Xbox and Microsoft to verify the claims. In response, Xbox referred us back to its Xbox Support page for updates on the outage.