diff --git a/etc/controlDict b/etc/controlDict
index 9a7a85017658a694766ce87a51fbf66b9b723567..5be9a1166468ae191aa9e67e01f47c4351a359a2 100644
--- a/etc/controlDict
+++ b/etc/controlDict
@@ -68,8 +68,8 @@ InfoSwitches
     allowSystemOperations   1;
 
     // Allow space character in fileName (use with caution)
-    // Default: 0 for non-Windows, 1 for Windows
-    //// allowSpaceInFileName    0;
+    // Ignored (always 1) for Windows.
+    allowSpaceInFileName    0;
 }
 
 
diff --git a/src/OpenFOAM/primitives/strings/fileName/fileName.C b/src/OpenFOAM/primitives/strings/fileName/fileName.C
index cedfa1cdee3b75a7118abd9940b5d49d750d05d6..35cdcc055312fa2e389a65aec446514d1b0873e6 100644
--- a/src/OpenFOAM/primitives/strings/fileName/fileName.C
+++ b/src/OpenFOAM/primitives/strings/fileName/fileName.C
@@ -42,7 +42,7 @@ int Foam::fileName::debug(Foam::debug::debugSwitch(fileName::typeName, 0));
 int Foam::fileName::allowSpaceInFileName
 (
     #ifdef _WIN32
-    Foam::debug::infoSwitch("allowSpaceInFileName", 1)
+    1  // Windows: expect spaces to occur
     #else
     Foam::debug::infoSwitch("allowSpaceInFileName", 0)
     #endif