Because UNIX/Linux file systems do not have a hidden file attribute, a file or folder is typically hidden by using a period as the first character in the filename, e.g. .hidden
If you are using an FTP server check the servers documentation to see if there is a setting that you must enable to have these files shown. Most FTP servers will hide these files by default unless you configure them to show the files.
If you are using a Samba file system you need to edit the smb.conf file and add the following line:
hide dot files = no