Can't flash Imagio from SD?

[Landlocked]

I've been able to successfully flash several times using RUU. I can't seem to get the phone to flash an updated ROM from my memory card -- stock ROM ir custom. I have the file named whiteimg.nbh (suggested in this forum) sitting there, but every attempt to flash from the bootloader just reloads the currently stored ROM and not what I cooked up. I'm in a real pickle because I cooked a bad ROM and now ActiveSync won't work on the Imagio so I can't use RUU again.

Thanks for your help!

Landlocked