i got a NEC ND-3540 about one year ago it was fine but now i have
cyclic redundancy check reading errors on some discs that i burnt with it
the discs have NO problem tested on 2 others drives, not a single problem.
but when reading with the NEC ND-3540 i get the cyclic redundancy check on some of the files.
how i fix that ? is updating the firmware solve the problem ? (i have v1.01)
did a disc scan and it was very good PIE max ~300, PIF max 5.

Your only chance is to re-burn those discs.

The other drives are ???

NEC drives in the past were not very good readers while being outstanding writers. Combined with not so good media would result in errors like yours. IMHO max PIE of 300 unless it was a single spike suggests that it was avarege or worse media.

Just as Chef said if you are concerned about loosing the data you should get decent media and burn new disk with it.

actually i use only verbatim (when i can find them) or philips or tdk media.
i dont want losing my comuter backup data.
the drives i extracted the date with are samsung and a lite-on.
yes it was one spike most disc at 15~30 PIE (test done at 16x)

actually im on the safe side i already have the files. however i want to know why the the NEC drive giving me the problem.(im pretty sure there is nothing wrong with the disc.)
is there a way to bypass the crc check ?
so i can then see with winrar if the file is really damaged.

Not that I am aware of that, luckily...

i reinstalled windows and i dont have the problem anymore (the other drives i tried are not on my computer).
sorry to trouble you everyone and thanks for the info and help
i wonder what caused it thou...

I am having a tough time understanding why reinstalling windows is an answer for crc errors. I do have crc issues, but only on certain movies from rental store.

That usually means some kind of copy protection involved.