help with loading mrb300

[_JoHnY_]

I hope someone can help me :

I went and loaded zcas2ucas to my MREV .

now i cant load mrb300 to my MREV

I am trying to use the UCAS loader but all I get is :
'Device not ready. Try to re-insert the CAM'

Please tell me there is something I can do to revert back to MREV