[Plugin: BackUpWordPress] strpos() & readdir() errors

Hi,

I installed BackUpWordpress by my back office and backup for SQL works perfectly.

The problem is for FTP BackUP.

In fact, when I select both save or only FTP, the plugin shows me:

Warning: strpos() [function.strpos]: Empty delimiter in /wp-content/plugins/backupwordpress/hm-backup/hm-backup.php on line 768

Warning: readdir(): supplied argument is not a valid Directory resource in /wp-content/plugins/backupwordpress/hm-backup/hm-backup.php on line 626
0 B. Backups will be compressed and should be smaller than this.

And impossible to save FTP.

Have u got a suggestion?
Best Regards

http://wordpress.org/extend/plugins/backupwordpress/