These are just a few ideas for dealing with read errors. I've mostly learned these from this forum so this is an aggregation, not original content. I'm posting it to help new users, like me, who might be frustrated by read errors.
This is just a very minor extension of this thread: viewtopic.php?f=8&t=15055
Tricks for discs that won’t read
- adjust retry to a high number, like 20 (I leave mine at 20 all the time)
..... View -> Preferences -> IO -> Read retry count
- clean discs with breath fog and microfiber cloth (radial wiping motion)
..... this helps a lot for used discs that have dirt and fingerprints
..... plus, I don’t like to mount dirty discs in my drive
..... I don't do this for discs just opened because cleaning can introduce the occasional scratch
..... wash cloths frequently as dirty cloths scratch discs (I only use a cloth on four discs before throwing it in with my wife's fine washables)
- use Pledge to fill in micro scratches
..... has worked on occasion but is not a silver bullet
..... let the pledge dry for a minute after spraying it so it can gel up a bit
- eject the disk from the drive and reload it
..... this works on occasion (just as successful as Pledge for me)
..... I will usually try this a couple of times
- try ripping in two different drives
..... this works on occasion
..... I'm not sure if the different drive has ever helped or if it is just the fact of re-mounting the disc in a drive hub (see previous note)
Relative Success
Before reading about and trying these various tricks, I had roughly a 60% success ratio on Blurays. It was discouraging because these discs played fine in my player. Using these techniques, my success ratio is roughly 95%.
There are three discs that I have owned for a few years, opened the celophane, put them into the drive, and they would not backup using any of the above tricks. These discs won't play cleanly in my player, either. I'm surprised at how many faulty Blurays there are.
Also, a bluray that is badly scratched is not going to backup or likely even play acceptably. If it looks like an ice skating rink after a playoff game, don’t expect much in terms of either backing up or playing. A badly scratched DVD has a much better chance of playing.
I hope this helps. If you have a technique to add to this list, please mention it and I will add it with proper credit.