updated for version 7.1-250
diff --git a/src/option.c b/src/option.c
index 6ff0a21..1d2f2aa 100644
--- a/src/option.c
+++ b/src/option.c
@@ -5671,7 +5671,7 @@
     {
 	if (gvarp == &p_fenc)
 	{
-	    if (!curbuf->b_p_ma)
+	    if (!curbuf->b_p_ma && opt_flags != OPT_GLOBAL)
 		errmsg = e_modifiable;
 	    else if (vim_strchr(*varp, ',') != NULL)
 		/* No comma allowed in 'fileencoding'; catches confusing it