diff --git a/truenas_install/__main__.py b/truenas_install/__main__.py
index 13104f4b..96b41aec 100644
--- a/truenas_install/__main__.py
+++ b/truenas_install/__main__.py
@@ -269,7 +269,7 @@ def main():
 
     old_root_dataset = None
     if old_root is not None:
-        for i in getmntinfo():
+        for i in getmntinfo().values():
             if i["mountpoint"] == old_root:
                 old_root_dataset = i["mount_source"]
                 break