Index: preset.php
===================================================================
RCS file: /cvsroot/moodle/moodle/mod/data/preset.php,v
retrieving revision 1.24.2.10
diff -u -r1.24.2.10 preset.php
--- mod/data/preset.php	24 Jun 2008 21:52:54 -0000	1.24.2.10
+++ mod/data/preset.php	25 Jun 2008 07:44:55 -0000
@@ -498,7 +498,7 @@
     }
 
     $exportfile = "$CFG->dataroot/$course->id/moddata/data/$data->id/$presetname.zip";
-    @unlink($exportfile);
+    file_exists($exportfile) && unlink($exportfile);
     $status = zip_files($filelist, $exportfile);
     // ToDo: status check
     foreach ($filelist as $file) {