diff --git a/src/platform/cocoamain.mm b/src/platform/cocoamain.mm
index b869994..e2676ff 100644
--- a/src/platform/cocoamain.mm
+++ b/src/platform/cocoamain.mm
@@ -1375,6 +1375,9 @@ int main(int argc, const char *argv[]) {
         dbp("%s", ([language UTF8String]));
         if(SolveSpace::SetLocale([language UTF8String])) break;
     }
+    if([languages count] == 0) {
+        SolveSpace::SetLocale("en_US");
+    }
 
     connexionInit();
     SolveSpace::SS.Init();
diff --git a/src/platform/w32main.cpp b/src/platform/w32main.cpp
index a5b9838..63080cf 100644
--- a/src/platform/w32main.cpp
+++ b/src/platform/w32main.cpp
@@ -1517,8 +1517,10 @@ int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
     }
 #endif
 
-    // Use the user default locale.
-    SetLocale((uint16_t)GetUserDefaultLCID());
+    // Use the user default locale, then fall back to English.
+    if(!SetLocale((uint16_t)GetUserDefaultLCID())) {
+        SetLocale("en_US");
+    }
 
     // Call in to the platform-independent code, and let them do their init
     SS.Init();