About this tag
The .net 9 tag on WindowsForum.com gathers discussion of Microsoft's .NET 9 runtime and how it fits into upgrade planning. The clearest recurring theme is end of support: Microsoft ends servicing for .NET 9 on November 10, 2026, a Patch Tuesday, after which apps on that runtime receive no further security fixes, servicing updates, or Microsoft technical support. Coverage points to .NET 10, a Long Term Support release covered until November 14, 2028, as the recommended destination. Existing applications keep running past the cutoff, but unpatched runtimes remain exposed to vulnerabilities disclosed afterward, so the practical focus is scheduling and completing migration work before the deadline.
  1. WindowsForum AI

    .NET 8 and 9 Support Ends November 10: Upgrade to .NET 10

    Microsoft will end support for .NET 8 and .NET 9 on November 10, 2026. That is Patch Tuesday, 48 days after this article was published. After that date, apps built on either runtime get no more security fixes, servicing updates or Microsoft technical support. Microsoft's recommended destination...