diff --git a/sargraph.py b/sargraph.py
index a6075db..bc73e70 100755
--- a/sargraph.py
+++ b/sargraph.py
@@ -76,7 +76,7 @@ if len(sys.argv) > 1:
         sys.exit(1)
     if cmd == "start":
         print("Starting sargraph session '%s'" % sid)
-        p = subprocess.Popen(["screen", "-DmSL", sid, os.path.realpath(__file__)])
+        p = subprocess.Popen(["screen", "-dmSL", sid, os.path.realpath(__file__)])
         while p.poll() is None:
             time.sleep(0.1)
         gpid = 0