diff --git a/src/EditorFeatures/CSharpTest/PdbSourceDocument/AbstractPdbSourceDocumentTests.cs b/src/EditorFeatures/CSharpTest/PdbSourceDocument/AbstractPdbSourceDocumentTests.cs
index c0f9e6a0b2a60..678b8b0fd99a4 100644
--- a/src/EditorFeatures/CSharpTest/PdbSourceDocument/AbstractPdbSourceDocumentTests.cs
+++ b/src/EditorFeatures/CSharpTest/PdbSourceDocument/AbstractPdbSourceDocumentTests.cs
@@ -155,15 +155,18 @@ protected static async Task GenerateFileAndVerifyAsync(
 
             var masWorkspace = service.TryGetWorkspace();
 
-            using var fileStream = File.OpenRead(file.FilePath);
-            var sourceText = SourceText.From(fileStream);
-            var text = SourceText.From(File.ReadAllText(file.FilePath));
-
             var pdbService = (PdbSourceDocumentMetadataAsSourceFileProvider)workspace.ExportProvider.GetExportedValues<IMetadataAsSourceFileProvider>().Single(s => s is PdbSourceDocumentMetadataAsSourceFileProvider);
 
-            var documentInfo = pdbService.GetTestAccessor().Documents[file.FilePath];
-            masWorkspace!.OnDocumentAdded(documentInfo.DocumentInfo);
-            var document = masWorkspace!.CurrentSolution.Projects.First().Documents.First(d => d.FilePath == file.FilePath);
+            // Add the document to the workspace.  We provide an empty static source text as the API requires it to open the document.
+            // We're not really trying to verify that the source text the editor hands to us is the right encoding - just that the document we added has the right encoding.
+            var result = pdbService.TryAddDocumentToWorkspace((MetadataAsSourceWorkspace)masWorkspace!, file.FilePath, new StaticSourceTextContainer(SourceText.From(string.Empty)), out _);
+            Assert.True(result);
+
+            // Immediately close the document so that we get the source text provided by the workspace (instead of the empty one we passed).
+            var info = pdbService.GetTestAccessor().Documents[file.FilePath];
+            masWorkspace!.OnDocumentClosed(info.DocumentId, new WorkspaceFileTextLoader(workspace.Services.SolutionServices, file.FilePath, info.Encoding));
+
+            var document = masWorkspace!.CurrentSolution.GetRequiredDocument(info.DocumentId);
 
             // Mapping the project from the generated document should map back to the original project
             var provider = workspace.ExportProvider.GetExportedValues<IMetadataAsSourceFileProvider>().OfType<PdbSourceDocumentMetadataAsSourceFileProvider>().Single();
@@ -339,7 +342,7 @@ protected static string GetPdbPath(string path)
         return Path.Combine(path, "reference.pdb");
     }
 
-    private class StaticSourceTextContainer(SourceText sourceText) : SourceTextContainer
+    protected class StaticSourceTextContainer(SourceText sourceText) : SourceTextContainer
     {
         public override SourceText CurrentText => sourceText;
 
diff --git a/src/EditorFeatures/CSharpTest/PdbSourceDocument/PdbSourceDocumentTests.cs b/src/EditorFeatures/CSharpTest/PdbSourceDocument/PdbSourceDocumentTests.cs
index 5b6456133778e..0d9bdc78c4013 100644
--- a/src/EditorFeatures/CSharpTest/PdbSourceDocument/PdbSourceDocumentTests.cs
+++ b/src/EditorFeatures/CSharpTest/PdbSourceDocument/PdbSourceDocumentTests.cs
@@ -951,4 +951,29 @@ await RunTestAsync(async path =>
             await GenerateFileAndVerifyAsync(project, symbol, Location.Embedded, source2.ToString(), expectedSpan, expectNullResult: false);
         });
     }
+
+    [Fact, WorkItem("https://github.com/dotnet/vscode-csharp/issues/7532")]
+    public async Task OpenFileWithDifferentCase()
+    {
+        var source = """
+            public class C
+            {
+                public int P { get; set; }
+            }
+            """;
+
+        await RunTestAsync(async path =>
+        {
+            var (project, symbol) = await CompileAndFindSymbolAsync(path, Location.Embedded, Location.Embedded, source, c => c.GetMember("C.P"));
+
+            using var workspace = (EditorTestWorkspace)project.Solution.Workspace;
+            var service = workspace.GetService<IMetadataAsSourceFileService>();
+            var file = await service.GetGeneratedFileAsync(project.Solution.Workspace, project, symbol, signaturesOnly: false, options: MetadataAsSourceOptions.Default, cancellationToken: CancellationToken.None);
+
+            var requestPath = file.FilePath.ToUpperInvariant();
+
+            var result = service.TryAddDocumentToWorkspace(requestPath, new StaticSourceTextContainer(SourceText.From(string.Empty)), out var documentId);
+            Assert.True(result);
+        });
+    }
 }
diff --git a/src/Features/Core/Portable/PdbSourceDocument/PdbSourceDocumentMetadataAsSourceFileProvider.cs b/src/Features/Core/Portable/PdbSourceDocument/PdbSourceDocumentMetadataAsSourceFileProvider.cs
index c0216482b1ca0..8ee8a4734d5a7 100644
--- a/src/Features/Core/Portable/PdbSourceDocument/PdbSourceDocumentMetadataAsSourceFileProvider.cs
+++ b/src/Features/Core/Portable/PdbSourceDocument/PdbSourceDocumentMetadataAsSourceFileProvider.cs
@@ -68,7 +68,7 @@ internal sealed class PdbSourceDocumentMetadataAsSourceFileProvider(
     /// generally run concurrently.  However, to be safe, we make this a concurrent dictionary to be safe to that
     /// potentially happening.
     /// </summary>
-    private readonly ConcurrentDictionary<string, SourceDocumentInfo> _fileToDocumentInfoMap = [];
+    private readonly ConcurrentDictionary<string, SourceDocumentInfo> _fileToDocumentInfoMap = new(StringComparer.OrdinalIgnoreCase);
 
     public async Task<MetadataAsSourceFile?> GetGeneratedFileAsync(
         MetadataAsSourceWorkspace metadataWorkspace,