Earlier this week, users of Legacy Update started reporting errors when checking for updates on Windows 7. The most common variant of this is error 80728015.
Rather than an error code, some users instead got a very misleading error dialog:
Windows Update cannot currently check for updates, because the service is not running. You may need to restart your computer.
We determined the cause to be a configuration file on Microsoft’s servers that reached its specified expiry date. The issue only affects installations of Windows that are enrolled in Microsoft Update, which enables Windows Update to receive updates for products such as Microsoft Office, Visual Studio, and SQL Server.
Microsoft corrected the issue two days later by bumping the expiry date from 2025-07-01 to 2033-07-01.
For more details about what happened, see my blog post: