PowerBuilder and .NET 8 End of Support: What to Do by 10 November 2026

On 10 November 2026 Microsoft ends support for .NET 8. From that date it no longer provides fixes, updates or online technical assistance for it, and it recommends uninstalling out-of-support versions you no longer use. For PowerBuilder teams this is already a practical question: a team with a frozen PowerBuilder 2025 application asked on the Appeon Community whether removing .NET 8 in November would affect it, because their security policy requires unsupported runtimes to go.

The answer depends on which PowerBuilder features you use, which line you are on and, for 2022 R3, even which maintenance build. Here is what needs .NET, which version, and the upgrade that keeps each line covered.

What ends on 10 November

.NET 8 is a long-term support release that shipped on 14 November 2023. It is now in Microsoft's maintenance phase, the final six months of support, when releases are updated to mitigate security vulnerabilities only; the latest patch, 8.0.31, came out on 8 September 2026. On 10 November 2026 .NET 8 goes out of support, on the same day as .NET 9. .NET 10, the current long-term support release, is supported until 14 November 2028. Microsoft's support policy warns that using out-of-support versions may put applications, their data and the computing environment at risk.

Installing .NET 10 does not cover a .NET 8 dependency

A framework-dependent .NET component targets a major version of the runtime. Microsoft's host picks the latest installed patch of that version and can move to a newer minor release, but by default it does not jump to a new major version: in Microsoft's own example, an application that targets 3.0 on a machine with only 5.0 installed shows an error instead of running.

The roll-forward behaviour can be changed — in the project, in the runtimeconfig.json file, with the DOTNET_ROLL_FORWARD environment variable or on the command line — but we found no Appeon guidance that uses it to run PowerBuilder's .NET 8 features on .NET 10. Plan for the runtime version Appeon documents for your build.

What in PowerBuilder needs .NET

For client/server applications, Appeon's deployment documentation does not ask for .NET across the board. It lists specific features that need the .NET Desktop Runtime on the user's machine, and the version depends on the line and the build:

Numbers are the .NET Desktop Runtime version Appeon lists for each feature; not listed means the feature is not on that version's list.

Two more places depend on .NET. On developer machines, PowerBuilder 2025 requires the .NET 8.0 SDK and 2025 R2 the .NET 10 SDK, and Appeon's troubleshooting guide notes that the IDE fails to start when the corresponding .NET SDK is missing. On the server side, PowerServer Web APIs run on .NET: PowerServer 2025 targets .NET 6.0 or 8.0, 2025 R2 adds .NET 10, and the ASP.NET Core Hosting Bundle on IIS must match the .NET version the Web APIs use.

Treat the list as a starting point. Answering exactly this question on the Appeon Community, Appeon's Armeen Mazda named DataWindow SaveAs and the ADO.NET interface, and added that “there could be some more things”. Test on a machine that has only .NET 10 installed before anyone removes .NET 8.

Your path, by version

Rolling out the .NET Desktop Runtime

Appeon is explicit that the PowerBuilder Runtime Packager does not include the .NET Desktop Runtime: you package and distribute it yourself, you can install its latest security patches once they are available, and its bitness (32-bit or 64-bit) must match your executable. A practical order of work:

1. List the applications that use ADO.NET, .NET assembly calls, MS Excel12 or the XPS blob, and the exact PowerBuilder build each one is deployed with.
2. Upgrade 2022 R3 applications to MR 3487 and 2025 applications to 2025 R2, moving the IDE and the runtime together.
3. Deploy .NET Desktop Runtime 10 in the bitness of each executable, on every client that runs those features.
4. For PowerServer, open the project in 2025 R2: the runtime version, target framework and NuGet package version upgrade automatically. Then redeploy in Full mode. Custom code and manually added NuGet packages are not upgraded for you.
5. Install the ASP.NET Core Hosting Bundle that matches the Web APIs' .NET version on each IIS server.
6. Keep the .NET 8.0 SDK on developer machines that still build PowerBuilder 2025 applications, or the IDE will not start.
7. Test on a machine with only .NET 10 installed, then agree the removal date for .NET 8 with your security team.

If an upgrade cannot happen before November

Keeping .NET 8 installed after 10 November means running a runtime that gets no further security fixes, which Microsoft says may put applications, data and the computing environment at risk. For a frozen application with a replacement already scheduled, that is a risk decision to take explicitly with your security team — documented, limited to the machines that need it, and with an end date — rather than something that happens by default.

What we would not rely on. Forcing PowerBuilder's .NET 8 features onto .NET 10 with roll-forward settings, or copying the runtime next to the application instead of installing it: we found no Appeon documentation for either approach.