diff --git a/antarest/study/model.py b/antarest/study/model.py
index a9e0cea4e7..a07be97d1a 100644
--- a/antarest/study/model.py
+++ b/antarest/study/model.py
@@ -15,7 +15,7 @@
 import secrets
 import uuid
 from datetime import datetime, timedelta
-from pathlib import Path, PurePath
+from pathlib import Path, PurePath, PurePosixPath
 from typing import TYPE_CHECKING, Annotated, Any, Dict, List, Mapping, Optional, Tuple, cast
 
 from antares.study.version import StudyVersion
@@ -358,7 +358,7 @@ class NonStudyFolderDTO(AntaresBaseModel):
     so the user can navigate in the hierarchy
     """
 
-    path: Path
+    path: PurePosixPath
     workspace: str
     name: str
     has_children: bool = Field(
@@ -368,7 +368,7 @@ class NonStudyFolderDTO(AntaresBaseModel):
     model_config = ConfigDict(populate_by_name=True)
 
     @computed_field(alias="parentPath")
-    def parent_path(self) -> Path:
+    def parent_path(self) -> PurePosixPath:
         """
         This computed field is convenient for the front.
 
@@ -376,10 +376,17 @@ def parent_path(self) -> Path:
 
         Returns: the parent path of the current directory. Starting with the workspace as a root directory (we want /workspafe/folder1/sub... and not workspace/folder1/fsub... ).
         """
-        workspace_path = Path(f"/{self.workspace}")
+        workspace_path = PurePosixPath(f"/{self.workspace}")
         full_path = workspace_path.joinpath(self.path)
         return full_path.parent
 
+    @field_validator("path", mode="before")
+    def to_posix(cls, path: Path) -> PurePosixPath:
+        """
+        Always convert path to posix path.
+        """
+        return PurePosixPath(path)
+
 
 class WorkspaceMetadata(AntaresBaseModel):
     """
diff --git a/antarest/study/storage/explorer_service.py b/antarest/study/storage/explorer_service.py
index d312f84552..b06534c008 100644
--- a/antarest/study/storage/explorer_service.py
+++ b/antarest/study/storage/explorer_service.py
@@ -11,6 +11,7 @@
 # This file is part of the Antares project.
 
 import logging
+from pathlib import PurePosixPath
 from typing import List
 
 from antarest.core.config import Config
@@ -48,7 +49,7 @@ def list_dir(
                 try:
                     if is_non_study_folder(child, workspace.filter_in, workspace.filter_out):
                         # we don't want to expose the full absolute path on the server
-                        child_rel_path = child.relative_to(workspace.path)
+                        child_rel_path = PurePosixPath(child.relative_to(workspace.path))
                         has_children = has_non_study_folder(child, workspace.filter_in, workspace.filter_out)
                         directories.append(
                             NonStudyFolderDTO(
diff --git a/tests/storage/business/test_explorer_service.py b/tests/storage/business/test_explorer_service.py
index 60f5e20f1d..5e403cf39c 100644
--- a/tests/storage/business/test_explorer_service.py
+++ b/tests/storage/business/test_explorer_service.py
@@ -110,6 +110,9 @@ def test_list_dir_several_subfolders(config_scenario_a: Config):
         in result
     )
 
+    assert str(result[0].path) == result[0].path.as_posix()
+    assert str(result[0].parent_path) == result[0].parent_path.as_posix()
+
 
 @pytest.mark.unit_test
 def test_list_dir_in_empty_folder(config_scenario_a: Config):