Erase the NAND using the serial flasher

Hi Morgan, thanks for your answer.

Follow is the link to the process that i m trying to do.
I have completed the process many times succesfully, but now i m getting that message and i do not what to do.

Thank you very much for your help

Just to explain a little bit.
I solder the adapter to the board, i check the port, then i open the command prompt and type:
sfh_DM36x.exe -nandflash -v -p "COMXX" dm6467_297_ubl.img uboot_
modifiedByGaucho.img
Sometimes it shows " boot me boot me " and then i do ctrl_c and type again, but now all the time finishes with " interface to the DM36x via UART failed " and i have read that erasing the Nand could fix.