diff --git a/codeflash/languages/function_optimizer.py b/codeflash/languages/function_optimizer.py
index 378b1a15f..b348a6e46 100644
--- a/codeflash/languages/function_optimizer.py
+++ b/codeflash/languages/function_optimizer.py
@@ -2794,13 +2794,13 @@ class FunctionOptimizer:
             if coverage_results and coverage_results.status == CoverageStatus.NOT_FOUND:
                 # File was not found in coverage data - likely excluded by test framework config
                 logger.warning(
-                    f"No coverage data found for {self.function_to_optimize.source_file_path}. "
+                    f"No coverage data found for {self.function_to_optimize.file_path}. "
                     f"This file may be excluded from coverage collection by your test framework configuration "
                     f"(e.g., coverage.exclude in vitest.config.ts for Vitest, or testMatch/coveragePathIgnorePatterns "
                     f"for Jest). Tests ran successfully but coverage cannot be measured."
                 )
                 return Failure(
-                    f"Coverage data not found for {self.function_to_optimize.source_file_path}. "
+                    f"Coverage data not found for {self.function_to_optimize.file_path}. "
                     f"The file may be excluded from coverage by your test framework config. "
                     f"Check coverage.exclude patterns in vitest.config.ts or jest.config.js."
                 )
diff --git a/tests/languages/test_coverage_exclusion_message.py b/tests/languages/test_coverage_exclusion_message.py
new file mode 100644
index 000000000..c196c6bc5
--- /dev/null
+++ b/tests/languages/test_coverage_exclusion_message.py
@@ -0,0 +1,45 @@
+"""Test for coverage exclusion error message (Bug #5 regression test)."""
+
+from pathlib import Path
+
+from codeflash.models.function_types import FunctionToOptimize
+from codeflash.models.models import CodePosition
+
+
+def test_function_to_optimize_has_file_path_not_source_file_path():
+    """Test that FunctionToOptimize has file_path attribute, not source_file_path.
+
+    Regression test for Bug #5: Bug #1's fix used wrong attribute name 'source_file_path'
+    instead of 'file_path', causing AttributeError when constructing coverage error messages.
+
+    The bug occurred in function_optimizer.py lines 2797 and 2803:
+        f"No coverage data found for {self.function_to_optimize.source_file_path}."
+
+    This should be:
+        f"No coverage data found for {self.function_to_optimize.file_path}."
+
+    Trace ID: 5c4a75fb-d8eb-4f75-9e57-893f0c44b9c7
+    """
+    # Create a FunctionToOptimize object
+    func = FunctionToOptimize(
+        function_name="testFunc",
+        file_path=Path("/workspace/target/src/test.ts"),
+        starting_line=1,
+        ending_line=10,
+        code_position=CodePosition(line_no=1, col_no=0),
+        file_path_relative_to_project_root="src/test.ts",
+    )
+
+    # Verify correct attribute exists
+    assert hasattr(func, "file_path"), "FunctionToOptimize should have 'file_path' attribute"
+    assert func.file_path == Path("/workspace/target/src/test.ts")
+
+    # Verify wrong attribute does NOT exist
+    assert not hasattr(
+        func, "source_file_path"
+    ), "FunctionToOptimize should NOT have 'source_file_path' attribute (it's a typo/bug)"
+
+    # Verify we can access file_path in string formatting (like the bug location does)
+    error_message = f"No coverage data found for {func.file_path}."
+    assert "test.ts" in error_message
+    # This should NOT raise AttributeError