diff --git a/src/testdir/test_gui.vim b/src/testdir/test_gui.vim
index a249145..b9b6bd8 100644
--- a/src/testdir/test_gui.vim
+++ b/src/testdir/test_gui.vim
@@ -1607,12 +1607,15 @@
 endfunc
 
 func Test_gui_dialog_file()
+  " make sure the file does not exist, otherwise a dialog makes Vim hang
+  call delete('Xdialfile')
+
   let lines =<< trim END
     file Xdialfile
     normal axxx
     confirm qa
   END
-  call writefile(lines, 'Xlines')
+  call writefile(lines, 'Xlines', 'D')
   let prefix = '!'
   if has('win32')
     let prefix = '!start '
@@ -1624,7 +1627,6 @@
 
   call delete('Xdialog')
   call delete('Xdialfile')
-  call delete('Xlines')
 endfunc
 
 " Test for sending low level key presses