@@ -120,14 +120,14 @@ async def post_users(request):
         async def listuserdata(request):
             directory = request.rel_url.query.get('dir', '')
             if not directory:
-                return web.Response(status=400)
+                return web.Response(status=400, text="Directory not provided")
 
             path = self.get_request_user_filepath(request, directory)
             if not path:
-                return web.Response(status=403)
+                return web.Response(status=403, text="Invalid directory")
 
             if not os.path.exists(path):
-                return web.Response(status=404)
+                return web.Response(status=404, text="Directory not found")
 
             recurse = request.rel_url.query.get('recurse', '').lower() == "true"
             full_info = request.rel_url.query.get('full_info', '').lower() == "true"
@@ -143,17 +143,21 @@ async def listuserdata(request):
             if full_info:
                 results = [
                     {
-                        'path': os.path.relpath(x, path),
+                        'path': os.path.relpath(x, path).replace(os.sep, '/'),
                         'size': os.path.getsize(x),
                         'modified': os.path.getmtime(x)
                     } for x in results if os.path.isfile(x)
                 ]
             else:
-                results = [os.path.relpath(x, path) for x in results if os.path.isfile(x)]
+                results = [
+                    os.path.relpath(x, path).replace(os.sep, '/')
+                    for x in results
+                    if os.path.isfile(x)
+                ]
 
             split_path = request.rel_url.query.get('split', '').lower() == "true"
             if split_path and not full_info:
-                results = [[x] + x.split(os.sep) for x in results]
+                results = [[x] + x.split('/') for x in results]
 
             return web.json_response(results)
 
 
@@ -2,6 +2,7 @@
 import os
 from aiohttp import web
 from app.user_manager import UserManager
+from unittest.mock import patch
 
 pytestmark = (
     pytest.mark.asyncio
@@ -53,7 +54,7 @@ async def test_listuserdata_recursive(aiohttp_client, app, tmp_path):
     client = await aiohttp_client(app)
     resp = await client.get("/userdata?dir=test_dir&recurse=true")
     assert resp.status == 200
-    assert set(await resp.json()) == {"file1.txt", os.path.join("subdir", "file2.txt")}
+    assert set(await resp.json()) == {"file1.txt", "subdir/file2.txt"}
 
 
 async def test_listuserdata_full_info(aiohttp_client, app, tmp_path):
@@ -80,11 +81,40 @@ async def test_listuserdata_split_path(aiohttp_client, app, tmp_path):
     resp = await client.get("/userdata?dir=test_dir&recurse=true&split=true")
     assert resp.status == 200
     assert await resp.json() == [
-        [os.path.join("subdir", "file1.txt"), "subdir", "file1.txt"]
+        ["subdir/file1.txt", "subdir", "file1.txt"]
     ]
 
 
 async def test_listuserdata_invalid_directory(aiohttp_client, app):
     client = await aiohttp_client(app)
     resp = await client.get("/userdata?dir=")
     assert resp.status == 400
+
+
+async def test_listuserdata_normalized_separator(aiohttp_client, app, tmp_path):
+    os_sep = "\\"
+    with patch("os.sep", os_sep):
+        with patch("os.path.sep", os_sep):
+            os.makedirs(tmp_path / "test_dir" / "subdir")
+            with open(tmp_path / "test_dir" / "subdir" / "file1.txt", "w") as f:
+                f.write("test content")
+
+            client = await aiohttp_client(app)
+            resp = await client.get("/userdata?dir=test_dir&recurse=true")
+            assert resp.status == 200
+            result = await resp.json()
+            assert len(result) == 1
+            assert "/" in result[0]  # Ensure forward slash is used
+            assert "\\" not in result[0]  # Ensure backslash is not present
+            assert result[0] == "subdir/file1.txt"
+
+            # Test with full_info
+            resp = await client.get(
+                "/userdata?dir=test_dir&recurse=true&full_info=true"
+            )
+            assert resp.status == 200
+            result = await resp.json()
+            assert len(result) == 1
+            assert "/" in result[0]["path"]  # Ensure forward slash is used
+            assert "\\" not in result[0]["path"]  # Ensure backslash is not present
+            assert result[0]["path"] == "subdir/file1.txt"