After installing VS2026 all Builds fail with CSC : error CS2016: Code page '1252' is invalid or not installed #81381
Description
Created from https://devdiv.visualstudio.com/DevDiv/_workitems/edit/2642554
This issue has been moved from a ticket on Developer Community.
[severity:I'm unable to use this version] [regression] [worked-in:2022]
We have a codebase that has <CodePage>1252</CodePage> set in all .NET-Projects. Codebase ist 50% C# with TargetFramework net48 and SDK-Style, 50% C++. Since installing the Visual Studio 2026 official release, all Visual Studios fail to build .NET-Projects with the Error
CSC : error CS2016: Code page '1252' is invalid or not installed
I have reproduced the error with a fresh VM and only Visual Studio 2026 installed, creating a Hello World Console project in .NET Framework and only converting the project to SDK-Style and setting the codepage to 1252. That also does not build. If I don't use an SDK-style project everything works as intended.
The codepage is installed, I can set it on the terminal. An ASAP fix is required.
I have included a project for minimal effort replication.
Original Comments
Feedback Bot on 11/20/2025, 00:23 AM:
We have directed your feedback to the appropriate engineering team for further evaluation. The team will review the feedback and notify you about the next steps.
Feedback Bot on 11/20/2025, 11:37 AM:
This issue is currently being investigated. Our team will get back to you if either more information is needed, a workaround is available, or the issue is resolved.
Jared Parsons [MSFT] on 11/20/2025, 11:53 AM:
I’m sorry that you ran into this problem. Thanks for providing that simplified repro for us to look at. I believe we know the underlying problem here and we’ll be working to address this. In the meantime can you try adding the following to your Directory.Build.props file and it should let you work around it.
<RoslynCompilerType>Framework</RoslynCompilerType>