I am having a problem on two different servers, both are running sql 2014. The maintenance plan does not delete the older backups. I have checked the permissions and the formatting and everything is correct. During troubleshooting I ran the xp_delete_file command to delete a single backup file. I got the error "Error executing xp_delete_file extended stored procedure: Specified file is not a SQL Server backup file." I ran a manual full backup and tried it again on that new backup file and received the same error.
I then copied a couple of the older transaction log files to a different server that was working correctly, ran the same script on them and the files were deleted.
Is there any way to force sql to recognize the backups that it makes as sql backups? The files are good, account used is sysadmin account, and file permissions are not the problem.