diff --git a/sicvar.c b/sicvar.c
index f0ef44c7..6b5d50bd 100644
--- a/sicvar.c
+++ b/sicvar.c
@@ -55,7 +55,7 @@
     assert(pData);
     assert(fd);
     pVar = (pSicsVariable)pData;
-    if(pVar->iLock)
+    if(pVar->iLock || pVar->iAccessCode == usInternal)
     {
       return 1;
     }