The FTPExtensionMap.txt file (Windows) and the FTPExtensionMapMac.txt file (Macintosh) map filename extensions to FTP transfer modes (ASCII or BINARY).
Each line in each of the two files includes a filename extension (such as GIF) and either the word ASCII or the word BINARY, to indicate which of the two FTP transfer modes should be used when transferring a file with that extension. On the Macintosh, each line also includes a creator code (such as DmWr) and a file type (such as TEXT). When you download a file with the given filename extension on the Macintosh, Dreamweaver assigns the specified creator and file type to the file.
If a file that you are transferring doesn’t have a filename extension, Dreamweaver uses the BINARY transfer mode.
Dreamweaver cannot transfer files in Macbinary mode. If you need to transfer files in Macbinary mode, you must use another FTP client.
The following example shows a line (from the Macintosh file) that indicates that files with the extension .html should be transferred in ASCII mode:
HTML DmWr TEXT ASCII
In both the FTPExtensionMap.txt file and FTPExtensionMapMac.txt file (Macintosh), all elements on a given line are separated by tabs. The extension and the transfer mode are in uppercase letters.
To change a default setting, edit the file in a text editor.