diff --git a/aider/coders/editblock_coder.py b/aider/coders/editblock_coder.py
index 0683daeaf..bbc5bcae5 100644
--- a/aider/coders/editblock_coder.py
+++ b/aider/coders/editblock_coder.py
@@ -532,12 +532,9 @@ def find_filename(lines, fence, valid_fnames):
         if not line.startswith(fence[0]):
             break
 
-    if not len(filenames):
+    if not filenames:
         return
 
-    if len(filenames) == 1:
-        return filenames[0]
-
     # pick the *best* filename found
 
     # Check for exact match first
@@ -553,7 +550,7 @@ def find_filename(lines, fence, valid_fnames):
 
     # Perform fuzzy matching with valid_fnames
     for fname in filenames:
-        close_matches = difflib.get_close_matches(fname, valid_fnames, n=1, cutoff=0.6)
+        close_matches = difflib.get_close_matches(fname, valid_fnames, n=1, cutoff=0.8)
         if len(close_matches) == 1:
             return close_matches[0]
 
@@ -562,7 +559,8 @@ def find_filename(lines, fence, valid_fnames):
         if "." in fname:
             return fname
 
-    return filenames[0] if filenames else None
+    if filenames:
+        return filenames[0]
 
 
 def find_similar_lines(search_lines, content_lines, threshold=0.6):
diff --git a/tests/basic/test_editblock.py b/tests/basic/test_editblock.py
index 1b099553c..61d3c8668 100644
--- a/tests/basic/test_editblock.py
+++ b/tests/basic/test_editblock.py
@@ -18,23 +18,19 @@ class TestUtils(unittest.TestCase):
 
     def test_find_filename(self):
         fence = ("```", "```")
-        valid_fnames = ["file1.py", "file2.py", "dir/file3.py"]
+        valid_fnames = ["file1.py", "file2.py", "dir/file3.py", "\windows\__init__.py"]
 
         # Test with filename on a single line
         lines = ["file1.py", "```"]
         self.assertEqual(eb.find_filename(lines, fence, valid_fnames), "file1.py")
 
-        # Test with filename and fence on separate lines
-        lines = ["file2.py", "```", "some content"]
-        self.assertEqual(eb.find_filename(lines, fence, valid_fnames), "file2.py")
-
         # Test with filename in fence
         lines = ["```python", "file3.py", "```"]
         self.assertEqual(eb.find_filename(lines, fence, valid_fnames), "dir/file3.py")
 
         # Test with no valid filename
         lines = ["```", "invalid_file.py", "```"]
-        self.assertIsNone(eb.find_filename(lines, fence, valid_fnames))
+        self.assertEqual("invalid_file.py", eb.find_filename(lines, fence, valid_fnames))
 
         # Test with multiple fences
         lines = ["```python", "file1.py", "```", "```", "file2.py", "```"]
@@ -48,6 +44,10 @@ class TestUtils(unittest.TestCase):
         lines = ["file1_py", "```"]
         self.assertEqual(eb.find_filename(lines, fence, valid_fnames), "file1.py")
 
+        # Test with fuzzy matching
+        lines = ["\windows__init__.py", "```"]
+        self.assertEqual(eb.find_filename(lines, fence, valid_fnames), "\windows\__init__.py")
+
     # fuzzy logic disabled v0.11.2-dev
     def __test_replace_most_similar_chunk(self):
         whole = "This is a sample text.\nAnother line of text.\nYet another line.\n"