diff --git a/src/datajoint/storage.py b/src/datajoint/storage.py
index 39a21ce46..4069212fb 100644
--- a/src/datajoint/storage.py
+++ b/src/datajoint/storage.py
@@ -418,7 +418,7 @@ def _full_path(self, path: str | PurePosixPath) -> str:
         elif self.protocol == "file":
             location = self.spec.get("location", "")
             if location:
-                return str(Path(location) / path)
+                return (Path(location) / path).as_posix()
             return path
         else:
             return self._require_adapter().full_path(self.spec, path)
diff --git a/tests/unit/test_storage_adapter.py b/tests/unit/test_storage_adapter.py
index a8ef4a99a..38a9d31f7 100644
--- a/tests/unit/test_storage_adapter.py
+++ b/tests/unit/test_storage_adapter.py
@@ -1,14 +1,17 @@
 """Tests for the StorageAdapter plugin system."""
 
+from pathlib import PureWindowsPath
+
 import pytest
 
 import datajoint as dj
+from datajoint import storage
 from datajoint.errors import DataJointError
 from datajoint.storage import StorageBackend
 from datajoint.storage_adapter import (
+    _COMMON_STORE_KEYS,
     StorageAdapter,
     _adapter_registry,
-    _COMMON_STORE_KEYS,
     get_storage_adapter,
 )
 
@@ -193,6 +196,17 @@ def test_unsupported_protocol_get_url_raises(self):
         with pytest.raises(DataJointError, match="Unsupported storage protocol"):
             backend.get_url("schema/file.dat")
 
+    def test_file_protocol_full_path_uses_forward_slashes(self, monkeypatch):
+        """`_full_path` must return forward slashes to match fsspec's walk()
+        output (gc.py relies on this for string-prefix stripping)."""
+        # monkeypatch to PureWindowsPath so that the test is platform-independent
+        monkeypatch.setattr(storage, "Path", PureWindowsPath)
+        backend = StorageBackend.__new__(StorageBackend)
+        backend.spec = {"protocol": "file", "location": "data\\blobs"}
+        backend.protocol = "file"
+        result = backend._full_path("schema/ab/cd/hash123")
+        assert result == "data/blobs/schema/ab/cd/hash123"
+
 
 class TestGetStoreSpecPluginDelegation:
     """Tests for plugin protocol handling in Config.get_store_spec()."""