diff --git a/ng/ngpkg.cpp b/ng/ngpkg.cpp
index a6d64928..750105c9 100644
--- a/ng/ngpkg.cpp
+++ b/ng/ngpkg.cpp
@@ -121,8 +121,8 @@ namespace netgen
 
 
 
-  char * err_needsmesh = (char*) "This operation needs a mesh";
-  char * err_jobrunning = (char*) "Meshing Job already running";
+  extern char * err_needsmesh;// = (char*) "This operation needs a mesh";
+  extern char * err_jobrunning;// = (char*) "Meshing Job already running";