There is really only a couple of reasons your attempt to upgrade firmware will do nothing, one is you have the current or more current firmware than you downloaded and the other is the player does not recognize the firmware file and thus will not attempt it.
It can be a finaky process, you have to follow the directions to the letter. You should take this to the Samsung forum where there are a lot of experienced people with that brand as well as company tech support or just call them.
The fact that a Blu-Ray disc that used to work does not now is not a good sign, this would not likely be firmware related, you may just have a broken player.
Have you tried a cleaning disc for the player, if not get one specifically for Blu-Ray players the head rides a lot closer to the disc so you want a head cleaner made for Blu-Ray. It does not take much dust/grease/smoke residue to take out a Blu-Ray head, however I have found cleaning them with a good head cleaner has worked more than 50% of the times I have done for people.
For some reason my Samsung BDP1500 Blu ray player has suddenly decided to stop playing Blu ray discs.
We hired a couple of Blu Ray discs from the video store and they would not play, thought it may have been discs so i tried a Blu Ray disc that has worked before and this also does not play, the Menu screen on the front of the machine just reads LOAD.
It will play normal dvd's.
I have been on the samsung website to get a firmware update, i downloaded the files to a usb, i put the usb stick in the DVD player and Zilch, am i doing something wrong that the firmware won't work.
Any suggestion would be greatly appreciated.

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