Microsoft App Center has been down for nearly a day, and no word on when it'll end

Updated If you're wondering why Microsoft's Visual Studio App Center isn't working, it's not just you: The service's login portal went down yesterday a little before 2200 UTC, and as of writing - nearly 18 hours on - Microsoft says the issue still hasn't been fully resolved.

Redmond has been mostly quiet on the issue, only saying that the AppCenter portal was unavailable in a VS App Center Status Page post yesterday at 2147 UTC. In an update today at 1514 UTC, Microsoft said it had taken mitigation steps, but noted further outages may occur. 

"As of now, our portal is accessible and we're actively monitoring the situation. Thank you for your patience and understanding," Microsoft said.

App Center is Microsoft's continuous integration platform for building and testing iOS, Android, Windows and macOS apps - think of it as the app-only version of Azure DevOps. Whenever users commit code changes to connected repositories hosted on GitHub, Azure or other services, App Center triggers an automatic build and testing process on cloud-hosted devices. 

As one Twitter user pointed out in response to Microsoft's tweet regarding the outage, it wasn't only the login portal that was down - API endpoints were also dead, as was the domain used to install App Center test apps. 

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Another Twitter user said they received a client network socket error indicating a disconnect before a secure TLS connection was established.

Currently, the App Center's status page shows that build, test, distribute, diagnostics, analytics and account management functions are all apparently operational, but that the App Center web portal is still experiencing degraded performance. Twitter users have reported that the portal still isn't working properly, and that other services are still down as well.

"Barely anything works," one response noted.

The developer community's relationship with App Center hasn't always been smooth. In 2020, Microsoft unceremoniously killed off the mobile backend-as-a-service component of VS App Center, upsetting developers who relied on it. 

We tried several different methods of getting in touch with Microsoft for more details, but haven't received a response. We'll update this story if we hear back. ®

Updated to add

Microsoft has told The Register that the problem is now sorted, although it still isn't saying what happened.