diff --git a/application/single_app/config.py b/application/single_app/config.py
index 47eebf17..d5ba49b6 100644
--- a/application/single_app/config.py
+++ b/application/single_app/config.py
@@ -88,7 +88,7 @@
 EXECUTOR_TYPE = 'thread'
 EXECUTOR_MAX_WORKERS = 30
 SESSION_TYPE = 'filesystem'
-VERSION = "0.237.010"
+VERSION = "0.237.011"
 
 SECRET_KEY = os.getenv('SECRET_KEY', 'dev-secret-key-change-in-production')
 
diff --git a/application/single_app/route_frontend_chats.py b/application/single_app/route_frontend_chats.py
index 8e34c0f4..a7f8e6a0 100644
--- a/application/single_app/route_frontend_chats.py
+++ b/application/single_app/route_frontend_chats.py
@@ -118,7 +118,8 @@ def upload_file():
         file.seek(0)
 
         filename = secure_filename(file.filename)
-        file_ext = os.path.splitext(filename)[1].lower()
+        file_ext = os.path.splitext(filename)[1].lower()  # e.g., '.png'
+        file_ext_nodot = file_ext.lstrip('.')              # e.g., 'png'
 
         with tempfile.NamedTemporaryFile(delete=False) as tmp_file:
             file.save(tmp_file.name)
@@ -131,9 +132,9 @@ def upload_file():
 
         try:
             # Check if this is an image file
-            is_image_file = file_ext in IMAGE_EXTENSIONS
+            is_image_file = file_ext_nodot in IMAGE_EXTENSIONS
             
-            if file_ext in ['.pdf', '.docx', '.pptx', '.ppt', '.html'] or is_image_file:
+            if file_ext_nodot in (DOCUMENT_EXTENSIONS | {'html'}) or is_image_file:
                 extracted_content_raw  = extract_content_with_azure_di(temp_file_path)
                 
                 # Convert pages_data list to string
@@ -191,25 +192,25 @@ def upload_file():
                         print(f"Warning: Vision analysis failed for chat upload: {vision_error}")
                         # Continue without vision analysis
                 
-            elif file_ext in ['.doc', '.docm']:
+            elif file_ext_nodot in {'doc', 'docm'}:
                 # Use docx2txt for .doc and .docm files
                 try:
                     import docx2txt
                     extracted_content = docx2txt.process(temp_file_path)
                 except ImportError:
                     return jsonify({'error': 'docx2txt library required for .doc/.docm files'}), 500
-            elif file_ext == '.txt':
+            elif file_ext_nodot == 'txt':
                 extracted_content  = extract_text_file(temp_file_path)
-            elif file_ext == '.md':
+            elif file_ext_nodot == 'md':
                 extracted_content  = extract_markdown_file(temp_file_path)
-            elif file_ext == '.json':
+            elif file_ext_nodot == 'json':
                 with open(temp_file_path, 'r', encoding='utf-8') as f:
                     parsed_json = json.load(f)
                     extracted_content  = json.dumps(parsed_json, indent=2)
-            elif file_ext in ['.xml', '.yaml', '.yml', '.log']:
+            elif file_ext_nodot in {'xml', 'yaml', 'yml', 'log'}:
                 # Handle XML, YAML, and LOG files as text for inline chat
                 extracted_content  = extract_text_file(temp_file_path)
-            elif file_ext in TABULAR_EXTENSIONS:
+            elif file_ext_nodot in TABULAR_EXTENSIONS:
                 extracted_content = extract_table_file(temp_file_path, file_ext)
                 is_table = True
             else:
diff --git a/docs/explanation/release_notes.md b/docs/explanation/release_notes.md
index 2381fa68..2b002285 100644
--- a/docs/explanation/release_notes.md
+++ b/docs/explanation/release_notes.md
@@ -2,10 +2,16 @@
 
 # Feature Release
 
-### **(v0.237.010)**
+### **(v0.237.011)**
 
 #### Bug Fixes
 
+*   **Chat File Upload "Unsupported File Type" Fix**
+    *   Fixed issue where uploading xlsx, png, jpg, csv, and other image/tabular files in the chat interface returned a 400 "Unsupported file type" error.
+    *   **Root Cause**: `os.path.splitext()` returns extensions with a leading dot (e.g., `.png`), but the `IMAGE_EXTENSIONS` and `TABULAR_EXTENSIONS` sets in `config.py` store extensions without dots (e.g., `png`). The comparison `'.png' in {'png', ...}` was always `False`, causing all image and tabular uploads to fall through to the unsupported file type error.
+    *   **Solution**: Added `file_ext_nodot = file_ext.lstrip('.')` and used the dot-stripped extension for set comparisons against `IMAGE_EXTENSIONS` and `TABULAR_EXTENSIONS`, matching the pattern already used in `functions_documents.py`.
+    *   (Ref: `route_frontend_chats.py`, file extension comparison, `IMAGE_EXTENSIONS`, `TABULAR_EXTENSIONS`)
+
 *   **Manage Group Page Duplicate Code and Error Handling Fix**
     *   Fixed multiple code quality and user experience issues in the Manage Group page JavaScript.
     *   **Duplicate Event Handlers**: Removed duplicate event handler registrations (lines 96-127) for `.select-user-btn`, `.remove-member-btn`, `.change-role-btn`, `.approve-request-btn`, and `.reject-request-btn` that were causing multiple event firings.