diff --git a/dev/src/host_win_winapi.cpp b/dev/src/host_win_winapi.cpp
index 8340cc5..c4cfb1f 100644
--- a/dev/src/host_win_winapi.cpp
+++ b/dev/src/host_win_winapi.cpp
@@ -25,6 +25,7 @@ namespace olc::host
 				if (!this->OnSystemThreadStart())
 				{
 					// PGE->OnContextStart() failed, or user aborted OnUserCreate()
+					systemActive = false; // Ensure Windows message loop exits
 					return;
 				}
 
diff --git a/olcPixelGameEngine3.h b/olcPixelGameEngine3.h
index 2a0e918..d223445 100644
--- a/olcPixelGameEngine3.h
+++ b/olcPixelGameEngine3.h
@@ -10756,6 +10756,7 @@ namespace olc::host
 				if (!this->OnSystemThreadStart())
 				{
 					// PGE->OnContextStart() failed, or user aborted OnUserCreate()
+					systemActive = false; // Ensure Windows message loop exits
 					return;
 				}