Brother NC-7100W - Manual (Page 131)

A - 7 APPENDIX
When you see "226 Data Transfer OK/Entering FirmWareUpdate
mode", you can be sure that the firmware file is being transferred to
the print server. If you do not see this message, the file you are
sending to the printer will either be ignored or the printer will print
garbage.
Reloading Using the FTP Protocol from a Web
Browser
Please visit the Brother Solutions Web site at http://
solutions.brother.com for more information on upgrading the print
server using a web browser.
You must use the "bin" command to put the FTP client into
Binary communications mode. If you do not specify the bin
command the upgrade process will not function correctly.