diff --git a/core/views/expo.py b/core/views/expo.py
index 3d7a318..57f6eb8 100644
--- a/core/views/expo.py
+++ b/core/views/expo.py
@@ -331,7 +331,7 @@ def editexpopage(request, path):
             # GIT see also core/models/cave.py writetrogglefile()
             # GIT see also core/views/uploads.py dwgupload()
             try:
-                with open(filepath.encode(sysdefaultencoding), "w") as f:
+                with open(os.path.normpath(filepath).encode(sysdefaultencoding), "w") as f:
                     print(f'WRITING{cwd}---{filename} ')
                     # as the wsgi process www-data, we have group write-access but are not owner, so cannot chmod.
                     # os.chmod(filepath, 0o664) # set file permissions to rw-rw-r--