diff --git a/src/filepath.c b/src/filepath.c
index 79eb7bf..49b814f 100644
--- a/src/filepath.c
+++ b/src/filepath.c
@@ -1929,7 +1929,8 @@
     }
     else
     {
-	semsg(_(e_invarg2), "writefile()");
+	semsg(_(e_invarg2),
+		_("writefile() first argument must be a List or a Blob"));
 	return;
     }
 
diff --git a/src/testdir/test_writefile.vim b/src/testdir/test_writefile.vim
index 5449071..497fa0b 100644
--- a/src/testdir/test_writefile.vim
+++ b/src/testdir/test_writefile.vim
@@ -16,6 +16,8 @@
   call assert_equal("morning", l[3])
   call assert_equal("vimmers", l[4])
   call delete(f)
+
+  call assert_fails('call writefile("text", "Xfile")', 'E475: Invalid argument: writefile() first argument must be a List or a Blob')
 endfunc
 
 func Test_writefile_ignore_regexp_error()
diff --git a/src/version.c b/src/version.c
index 83feed9..b709dbb 100644
--- a/src/version.c
+++ b/src/version.c
@@ -739,6 +739,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    404,
+/**/
     403,
 /**/
     402,