diff --git a/mystic/bbs_io.pas b/mystic/bbs_io.pas
index 80bca71..b2f686a 100644
--- a/mystic/bbs_io.pas
+++ b/mystic/bbs_io.pas
@@ -1276,7 +1276,7 @@ Begin
       InMacro := False;
 
   If TBBSCore(Core).CheckTimeOut Then
-    If TimerSeconds - TBBSCore(Core).TimeOut >= Config.Inactivity Then Begin
+    If (Config.Inactivity > 0) and (TimerSeconds - TBBSCore(Core).TimeOut >= Config.Inactivity) Then Begin
       TBBSCore(Core).SystemLog('Inactivity timeout');
       OutFullLn (TBBSCore(Core).GetPrompt(136));
       Halt(0);