diff --git a/core/kernel/kernel-tests.factor b/core/kernel/kernel-tests.factor
index 152e1bac14..7d5f7b538b 100644
--- a/core/kernel/kernel-tests.factor
+++ b/core/kernel/kernel-tests.factor
@@ -49,8 +49,11 @@ IN: kernel.tests
 
 : overflow-c ( -- ) overflow-c overflow-c ;
 
+! The VM cannot recover from callstack overflow on Windows or
+! OpenBSD, because no facility exists to run memory protection
+! fault handlers on an alternate callstack.
 os [ windows? ] [ openbsd? ] bi or [
-    [ overflow-c ] [ { "kernel-error" 14 f f } = ] must-fail-with
+    [ overflow-c ] [ { "kernel-error" 15 f f } = ] must-fail-with
 ] unless
 
 [ -7 <byte-array> ] must-fail
diff --git a/vm/errors.cpp b/vm/errors.cpp
index 21dff5a475..f6ceee9966 100755
--- a/vm/errors.cpp
+++ b/vm/errors.cpp
@@ -98,9 +98,9 @@ void factor_vm::memory_protection_error(cell addr, stack_frame *stack)
 	else if(ctx->retainstack_seg->overflow_p(addr))
 		general_error(ERROR_RETAINSTACK_OVERFLOW,false_object,false_object,stack);
 	else if(ctx->callstack_seg->underflow_p(addr))
-		general_error(ERROR_CALLSTACK_UNDERFLOW,false_object,false_object,stack);
-	else if(ctx->callstack_seg->overflow_p(addr))
 		general_error(ERROR_CALLSTACK_OVERFLOW,false_object,false_object,stack);
+	else if(ctx->callstack_seg->overflow_p(addr))
+		general_error(ERROR_CALLSTACK_UNDERFLOW,false_object,false_object,stack);
 	else
 		general_error(ERROR_MEMORY,allot_cell(addr),false_object,stack);
 }