diff --git a/autorest/black/__init__.py b/autorest/black/__init__.py
index 834ecf6139d..f572d575ef5 100644
--- a/autorest/black/__init__.py
+++ b/autorest/black/__init__.py
@@ -5,6 +5,7 @@
 # --------------------------------------------------------------------------
 import logging
 from pathlib import Path
+import os
 import black
 
 from .. import Plugin
@@ -21,6 +22,8 @@ def __init__(self, autorestapi):
         output_folder_uri = self._autorestapi.get_value("outputFolderUri")
         if output_folder_uri.startswith("file:"):
             output_folder_uri = output_folder_uri[5:]
+        if os.name == 'nt' and output_folder_uri.startswith("///"):
+            output_folder_uri = output_folder_uri[3:]
         self.output_folder = Path(output_folder_uri)
 
     def process(self) -> bool: