diff --git a/main.cpp b/main.cpp
index 3079d3846..d19cbeff9 100644
--- a/main.cpp
+++ b/main.cpp
@@ -3530,7 +3530,7 @@ void BitcoinMiner()
     SetThreadPriority(THREAD_PRIORITY_LOWEST);
     bool f4WaySSE2 = Detect128BitSSE2();
     if (mapArgs.count("-4way"))
-        f4WaySSE2 = GetBoolArg(mapArgs["-4way"]);
+        f4WaySSE2 = GetBoolArg("-4way");
 
     // Each thread has its own key and counter
     CReserveKey reservekey;