I need to change or disable cd boot checksum

[carollahany]

hi I am remastering knoppix 3.7

I need to change or disable cd boot checksum.
I added some files to the iso image and then burned the cd but it gives me
the error message:
image checksum error, sorry...

Boot failed: press a key to retry...

>>so...can anyone help...please...

thank you,
carolla.