diff --git a/archrepo2/repomon.py b/archrepo2/repomon.py
index e7efa37..e134a9c 100755
--- a/archrepo2/repomon.py
+++ b/archrepo2/repomon.py
@@ -92,12 +92,15 @@ class RepoMan:
       return
 
     logger.info('Running cmd: %r', cmd)
-    # have to specify io_loop or we'll get error tracebacks
+    # have to specify io_loop or we'll get error tracebacks in some versions
+    # of Tornado
     try:
       p = tornado.process.Subprocess(cmd, io_loop=self._ioloop)
-      p.set_exit_callback(partial(self.command_done, callbacks))
     except OSError:
       logger.error('failed to run command.', exc_info=True)
+      self.run_command()
+    else:
+      p.set_exit_callback(partial(self.command_done, callbacks))
 
   def command_done(self, callbacks, status):
     if status == 0: