Select, by file extension, file types that should always be transferred in ASCII mode.
On the menu bar, go to Tools > Global Options.
Expand Transfer.
Click ASCII Types.
Type the file extension for files you want to transfer in ASCII mode in this box.
Click the Add button and the extension will be added to the list.
Click the Remove button, and any extension highlighted in the list will be deleted.
You can specify a Transfer type from the main menu (see Transferring files in binary or ASCII mode). You can also specify a Transfer type for an individual site by highlighting the site in the Site Manager, clicking the Type tab, and choosing from the Transfer list. Auto is the default transfer type, and sends files in the mode specified for each file's extension. All extensions are sent in binary mode unless they are listed in theASCII Extensions list.