Visual Studio extension uses internal type removed in 2026

[ificator]

The BuildXL VS extension uses IVsSolutionBuildManagerPrivate.GetNextBuildItemForUIThread (from Microsoft.Internal.VisualStudio.Interop) to detect when the last project has registered its build filter, at which point it triggers the actual BuildXL build. Unfortunately the IVsSolutionBuildManagerPrivate type apperas to have been removed from the assembly in VS 2026 resulting in:

  <entry>
    <record>265</record>
    <time>2026/03/09 16:50:41.862</time>
    <type>Error</type>
    <source>VisualStudio</source>
    <description>SetSite failed for package [BuildXLVsPackage](null)</description>
    <guid>{76439C3A-9FAF-4F38-9F54-F127E9BE9171}</guid>
    <hr>0x80131522</hr>
    <errorinfo></errorinfo>
  </entry>

The type was confirmed using windbg:

0:000> !pe
Exception object: 000002345f44e138
Exception type:   System.TypeLoadException
Message:          Could not load type 'Microsoft.Internal.VisualStudio.Shell.Interop.IVsSolutionBuildManagerPrivate' from assembly 'Microsoft.Internal.VisualStudio.Interop, Version=18.0.0.0, Culture=neutral,
PublicKeyToken=b03f5f7f11d50a3a'.
InnerException:   <none>
StackTrace (generated):
<none>
StackTraceString: <none>
HResult: 80131522

[pgunasekara]

Hi @ificator, sorry about the late response! Since you are internal to microsoft, please use the BuildXL.Internal repo and build the internal version by adding the -internal flag which should get rid of that issue for you.