diff --git a/lightrag/api/routers/document_routes.py b/lightrag/api/routers/document_routes.py
index 39314233..d9dfe913 100644
--- a/lightrag/api/routers/document_routes.py
+++ b/lightrag/api/routers/document_routes.py
@@ -215,7 +215,27 @@ async def pipeline_enqueue_file(rag: LightRAG, file_path: Path) -> bool:
                 | ".scss"
                 | ".less"
             ):
-                content = file.decode("utf-8")
+                try:
+                    # Try to decode as UTF-8
+                    content = file.decode("utf-8")
+
+                    # Validate content
+                    if not content or len(content.strip()) == 0:
+                        logger.error(f"Empty content in file: {file_path.name}")
+                        return False
+
+                    # Check if content looks like binary data string representation
+                    if content.startswith("b'") or content.startswith('b"'):
+                        logger.error(
+                            f"File {file_path.name} appears to contain binary data representation instead of text"
+                        )
+                        return False
+
+                except UnicodeDecodeError:
+                    logger.error(
+                        f"File {file_path.name} is not valid UTF-8 encoded text. Please convert it to UTF-8 before processing."
+                    )
+                    return False
             case ".pdf":
                 if not pm.is_installed("pypdf2"):  # type: ignore
                     pm.install("pypdf2")
@@ -229,7 +249,7 @@ async def pipeline_enqueue_file(rag: LightRAG, file_path: Path) -> bool:
             case ".docx":
                 if not pm.is_installed("python-docx"):  # type: ignore
                     pm.install("docx")
-                from docx import Document
+                from docx import Document  # type: ignore
                 from io import BytesIO
 
                 docx_file = BytesIO(file)
@@ -238,7 +258,7 @@ async def pipeline_enqueue_file(rag: LightRAG, file_path: Path) -> bool:
             case ".pptx":
                 if not pm.is_installed("python-pptx"):  # type: ignore
                     pm.install("pptx")
-                from pptx import Presentation
+                from pptx import Presentation  # type: ignore
                 from io import BytesIO
 
                 pptx_file = BytesIO(file)
@@ -250,7 +270,7 @@ async def pipeline_enqueue_file(rag: LightRAG, file_path: Path) -> bool:
             case ".xlsx":
                 if not pm.is_installed("openpyxl"):  # type: ignore
                     pm.install("openpyxl")
-                from openpyxl import load_workbook
+                from openpyxl import load_workbook  # type: ignore
                 from io import BytesIO
 
                 xlsx_file = BytesIO(file)
diff --git a/lightrag/lightrag.py b/lightrag/lightrag.py
index b2e9845e..6f42003d 100644
--- a/lightrag/lightrag.py
+++ b/lightrag/lightrag.py
@@ -685,8 +685,24 @@ class LightRAG:
         all_new_doc_ids = set(new_docs.keys())
         # Exclude IDs of documents that are already in progress
         unique_new_doc_ids = await self.doc_status.filter_keys(all_new_doc_ids)
+
+        # Log ignored document IDs
+        ignored_ids = [
+            doc_id for doc_id in unique_new_doc_ids if doc_id not in new_docs
+        ]
+        if ignored_ids:
+            logger.warning(
+                f"Ignoring {len(ignored_ids)} document IDs not found in new_docs"
+            )
+            for doc_id in ignored_ids:
+                logger.warning(f"Ignored document ID: {doc_id}")
+
         # Filter new_docs to only include documents with unique IDs
-        new_docs = {doc_id: new_docs[doc_id] for doc_id in unique_new_doc_ids}
+        new_docs = {
+            doc_id: new_docs[doc_id]
+            for doc_id in unique_new_doc_ids
+            if doc_id in new_docs
+        }
 
         if not new_docs:
             logger.info("No new unique documents were found.")