dotnet · jjonescz · Nov 21, 2025 · Nov 21, 2025 · KalleOlaviNiemitalo · Nov 21, 2025
diff --git a/src/Cli/Microsoft.DotNet.FileBasedPrograms/FileBasedProgramsResources.resx b/src/Cli/Microsoft.DotNet.FileBasedPrograms/FileBasedProgramsResources.resx
@@ -169,4 +169,7 @@
     <value>Unrecognized directive '{0}'.</value>
     <comment>{0} is the directive name like 'package' or 'sdk'.</comment>
   </data>
-</root>
+  <data name="EmptyTempPath" xml:space="preserve">
+    <value>Unable to determine a temporary directory path. Consider configuring the TEMP environment variable on Windows or local app data folder on Unix.</value>
+  </data>
+</root>
diff --git a/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.cs.xlf b/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.cs.xlf
diff --git a/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.de.xlf b/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.de.xlf
diff --git a/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.es.xlf b/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.es.xlf
diff --git a/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.fr.xlf b/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.fr.xlf
diff --git a/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.it.xlf b/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.it.xlf
diff --git a/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.ja.xlf b/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.ja.xlf
diff --git a/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.ko.xlf b/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.ko.xlf
diff --git a/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.pl.xlf b/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.pl.xlf
diff --git a/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.pt-BR.xlf b/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.pt-BR.xlf
diff --git a/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.ru.xlf b/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.ru.xlf
diff --git a/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.tr.xlf b/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.tr.xlf
diff --git a/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.zh-Hans.xlf b/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.zh-Hans.xlf
diff --git a/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.zh-Hant.xlf b/src/Cli/Microsoft.DotNet.FileBasedPrograms/xlf/FileBasedProgramsResources.zh-Hant.xlf
diff --git a/src/Cli/dotnet/Commands/Run/VirtualProjectBuildingCommand.cs b/src/Cli/dotnet/Commands/Run/VirtualProjectBuildingCommand.cs
@@ -1132,6 +1132,11 @@ public static string GetTempSubdirectory()
             ? Path.GetTempPath()
             : Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
 
+        if (string.IsNullOrEmpty(directory))
+        {
+            throw new InvalidOperationException(FileBasedProgramsResources.EmptyTempPath);
+        }
+
         return Path.Join(directory, "dotnet", "runfile");
     }