I ran my backup today and noticed this issue in the WP admin during the backup. After the backup was complete the message appeared in the admin header area as well for a few page loads, but it seems to be gone now.
unlink(...mediatemple-server-details.../html/wp-content/uploads/.....-backups/.backup_warnings) [function.unlink]: No such file or directory in /....../html/wp-content/plugins/backupwordpress/classes/schedule.php on line 655
Also, not sure if this is related but in the backup folder error logs, this was created around the same time that I ran the backup I believe:
Undefined index: id ......./wp-content\/plugins\/easy-fancybox\/easy-fancybox.php, 351
I'm running BackUpWordPress 2.2.1 and WP 3.51 on a MediaTemple server. It should also be noted the site is running SuperCache as I know that can cause issues all over the place.
Anything I can do troubleshoot this, let me know! Thank you!