diff --git a/src/os/windows/win32.cpp b/src/os/windows/win32.cpp
--- a/src/os/windows/win32.cpp
+++ b/src/os/windows/win32.cpp
@@ -79,7 +79,7 @@ bool LoadLibraryList(Function proc[], co
 void ShowOSErrorBox(const char *buf, bool system)
 {
 	MyShowCursor(true);
-	MessageBox(GetActiveWindow(), OTTD2FS(buf), _T("Error!"), MB_ICONSTOP);
+	MessageBox(GetActiveWindow(), OTTD2FS(buf), _T("Error!"), MB_ICONSTOP | MB_TASKMODAL);
 }
 
 void OSOpenBrowser(const char *url)