diff --git a/tools/azure-sdk-tools/devtools_testutils/proxy_docker_startup.py b/tools/azure-sdk-tools/devtools_testutils/proxy_docker_startup.py
index 580dc299fcd07..362f393c4aa27 100644
--- a/tools/azure-sdk-tools/devtools_testutils/proxy_docker_startup.py
+++ b/tools/azure-sdk-tools/devtools_testutils/proxy_docker_startup.py
@@ -52,7 +52,7 @@ def parse_tag(file):
     except FileNotFoundError:
         # REPO_ROOT only gets us to /sdk/{service}/{package}/.tox/whl on Windows
         # REPO_ROOT only gets us to /sdk/{service}/{package}/.tox/whl/lib on Ubuntu
-        head, tail = os.path.split(os.getcwd())
+        head, tail = os.path.split(REPO_ROOT)
         while tail != "sdk":
             head, tail = os.path.split(head)