Ftal error schedule.php on line 671

First the plugin told me that the cron isn’t working so I have decided to remove it and now i get a blank scree when I try to remove the plugin with this line:
Fatal error: Class ‘HMBKP_Services’ not found in /xxxxxx/xxxxxx/xxxxxx/xxxxx/xxxxx/wp-content/plugins/backupwordpress/classes/schedule.php on line 671

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