"<enableserial>" was Disappeared from /cf/conf/config.xml file</enableserial>

[learnin9]

1:login the webGUI,and make "enable serial" from the sytsem–>advanced menu
2:find the "<enableserial>" from the /cf/conf/config.xml
3:vi /etc/platform file and modify the file as "embedded"
4:reboot the system
5:I can not find the "enable serial" from the system--->advanced menu
6:I submit button again the  system--->advanced menu
7:"<enableserial>" was Disappeared from /cf/conf/config.xml file
8: reboot system, I found the log messages screen from the VGA
why?</enableserial></enableserial>

[jimp]

Don't change the platform, that is not supported.

Embedded platform only has serial output, so the changes are likely assumed to be present.