Backup Tool "Cannot create target directory."

Backup Tool fails to create a backup and produces the following error: “Cannot create target directory. Please check whether you have enough permission.”  Where would I go to set the proper permissions?  And why would this message start appearing all of a sudden when the Backup Tool worked fine before.

Hi Steve,
backups are created in ‘…/Documents/eM Client’ folder, so check if you have writing permission for that folder from your current account.