diff --git a/win32ss/drivers/videoprt/resource.c b/win32ss/drivers/videoprt/resource.c
index cd85c9feb4..7c6bc79a8e 100644
--- a/win32ss/drivers/videoprt/resource.c
+++ b/win32ss/drivers/videoprt/resource.c
@@ -1060,7 +1060,7 @@ VideoPortSetTrappedEmulatorPorts(
 {
     UNIMPLEMENTED;
     /* Should store the ranges in the device extension for use by ntvdm. */
-    return NO_ERROR;
+    return ERROR_INVALID_PARAMETER;
 }
 
 /*