diff --git a/src/primaite/simulator/file_system/file_system.py b/src/primaite/simulator/file_system/file_system.py
index 3290570e..6cdcaca2 100644
--- a/src/primaite/simulator/file_system/file_system.py
+++ b/src/primaite/simulator/file_system/file_system.py
@@ -95,7 +95,13 @@ class FileSystem(SimComponent):
         :type: folder_name: str
         """
         folder = FileSystemFolder(name=folder_name)
-        self.folders[folder.uuid] = folder
+
+        if folder.uuid in self.folders:
+            # iterate until a folder with a non-matching uuid is added
+            # which is VERY unlikely but it'll be weird if it happens twice
+            return self.create_folder(folder_name=folder_name)
+        else:
+            self.folders[folder.uuid] = folder
         return folder
 
     def delete_file(self, file: Optional[FileSystemFile] = None):
diff --git a/src/primaite/simulator/file_system/file_system_folder.py b/src/primaite/simulator/file_system/file_system_folder.py
index 23f4ca79..62f98029 100644
--- a/src/primaite/simulator/file_system/file_system_folder.py
+++ b/src/primaite/simulator/file_system/file_system_folder.py
@@ -26,7 +26,7 @@ class FileSystemFolder(FileSystemItem):
             raise Exception(f"Invalid file: {file}")
 
         # check if file with id already exists in folder
-        if self.get_file_by_id(file.uuid) is not None:
+        if file.uuid in self.files:
             _LOGGER.debug(f"File with id {file.uuid} already exists in folder")
         else:
             # add to list