--- a/taskcluster/docker/recipes/run-task
+++ b/taskcluster/docker/recipes/run-task
@@ -542,17 +542,19 @@ def main(args):
             if e.errno != errno.EEXIST:
                 raise
 
         if running_as_root:
             os.chown(store_path, uid, gid)
 
     prepare_checkout_dir(args.vcs_checkout)
     prepare_checkout_dir(args.tools_checkout)
-    prepare_hg_store_path()
+    prepare_checkout_dir(args.comm_checkout)
+    if args.vcs_checkout or args.tools_checkout or args.comm_checkout:
+        prepare_hg_store_path()
 
     if running_as_root:
         # Drop permissions to requested user.
         # This code is modeled after what `sudo` was observed to do in a Docker
         # container. We do not bother calling setrlimit() because containers have
         # their own limits.
         print_line(b'setup', b'running as %s:%s\n' % (args.user, args.group))
         os.setgroups(gids)