Does anyone have a working post processor for BobCad ver 21 to a Bandit I level 3 controller? BobCad assistance has been trying, but can't get it to work correctly. Latest version seems to be sending illegal character.

Butcher,
BobCAD-CAM technical support has the post processor that you need. Call us at 727-489-0003 and ask for the link to download the post.
Sincerely,
CNC Dude

It may be a problem not with your post processor, so much as your comm settings. Bandit cannot use the % sign to start or end the transmission, so those characters need to be deleted either from your post, or from the comm setup.

Bandit does not need any character to start hardware communications. But, it is customary to use this at the start of your program:
N1&
to direct the Bandit to store at address line 1 in memory.

The end of the transmission is an ASCII character. But I have forgotten which one. Here are a few likely candidates to try:
@004
@017
@018 <----I think it is this one
@019
@020

I'm assuming that Bobcad communications still uses the @ sign to designate transmission of an ASCII char.