If the user the WholesaleBackup service is running as does not have read/write permissions on a file or folder it is trying to backup you will see "access is denied" errors in your backup logs.
Please visit http://technet.microsoft.com/en-us/library/bb727008.aspx for step by step instructions on how to interactively explore and set permissions for files and folders from Windows Explorer.
Please visit this article on accessing files and folders on network shares and mapped drives for more information about service users.
Example permissions problem as shown in new client
Error : access is denied (insufficient privileges); unable to open file \\?\C:\MyData\Boss\Confidential.doc for AES256 encryption.
Example permissions problem as shown in original client
Error, unable to open file for reading [\\?\C:\MyData\Boss\Confidential.doc] - access is denied, please change permissions on this file - System Error Code [5].