I have managed to get a manual download backup to work, but everything else seems to fail. Here is what I am seeing in the event logs:
For Manual Email option:
The backup failed: 2: fopen(/home/trailerc/public_html/wp-content/plugins/wponlinebackup/tmp/full/cdrbuffer.php) [function.fopen]: failed to open stream: No such file or directory
For Manual Online option:
The backup failed: The server failed to retrieve data from your blog. Please check your blog is not experiencing any network issues and try again later.
Any ideas on what is going on here? I have deactivated and deleted the plugin, and then reinstalled it to no success.