098ccf83fca73f074dfd27764f9835612b691db6
 iodbc/herr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/iodbc/herr.c b/iodbc/herr.c
index a721bf6..17f8620 100644
--- a/iodbc/herr.c
+++ b/iodbc/herr.c
@@ -1370,7 +1370,7 @@ SQLGetDiagField_Internal (
 	    {
 	      (*(SQLINTEGER *) pDiagInfoPtr) = 0;
 	      /* get the number from the driver */
-	      if (con)
+	      if (con  && con->henv)
 		{
                   CALL_UDRIVER(con, Handle, retcode, hproc, unicode_driver, en_GetDiagField,
                     (nHandleType, dhandle, 0, nDiagIdentifier,