software update

[neuroguy]

just bought a new raymarine es128 mfd, and color radar, es200 autopilot, cp470 and 1000 watt transducer. Had them installed by my mechanic. Trying to upgrade the software to version 17.45 but never works. I download it and it is an iso.zip file, which cannot be unzipped. I read somewhere where you do not have to unzip it. So formatted an sds chip and loaded it onto the chip. Followed the instructions on raymarine website to upgrade, but it never reads the chip and does not upload the new software. Seems like something like this ought to be simple yet keep running into problems. Any suggestions? Thanks very much...