You must set or CHMOD permissions on the ListMailPRO /attach sub-directory to 777 or read, write, & execute access for all users. This is to allow web-based upload of attachments and provides temporary storage for export and backup files. If you don't do this, you will need to upload your attachments manually and may not be able to use export or backup features.
It is usually possible to set the permissions on a file or folder using your FTP program. To do this, try right-clicking on the /attach folder and look for a CHMOD option. If this option is not present, try Properties. If your FTP program does not support this option, the permissions on the /attach folder will need to be changed using a shell. If you are unfamiliar with how to do this, contact your host and have them do it for you.
Security
To prevent unauthorized access of your attachment, export and backup files via the web, create a file named .htaccess in your /attach folder. (You may have to start with htaccess.txt, upload, then rename it remotely using FTP) The file should contain the following two lines:
Deny from All
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