About half of the DVD's tried have completed successfully

[manning]

Some movies work fine, some get about half way through saving and have an uncorrectable error. The latest one is below. I've also gotten the message that the file is corrupt or invalid.

Error 'Scsi error - MEDIUM ERROR:NO SEEK COMPLETE' occurred while reading '/VIDEO_TS/VTS_03_1.VOB' at offset '2584764416'
Error 'Scsi error - MEDIUM ERROR:L-EC UNCORRECTABLE ERROR' occurred while reading '/VIDEO_TS/VTS_03_1.VOB' at offset '2585372672'
Error 'Scsi error - MEDIUM ERROR:L-EC UNCORRECTABLE ERROR' occurred while reading '/VIDEO_TS/VTS_03_1.VOB' at offset '2585372672'
Failed to save title 0 to file E://title00.mkv
0 titles saved, 1 failed

[crowfax]

This is not a MakeMKV issue. That is a message from your DVD drive telling you it's unable to read the disc.

Your disc might be poorly damaged / dirty. However you say this is happening on half your DVD's, this means your drive might be failing, or your have a bad cable between your drive and your motherboard.

[manning]

I've had the same results on all three of my pc's, so I assumed it wasn't a drive issue. But if this is not a software issue perhaps I should try to replace one of my drives. Same thing with the "corrupt or invalid" error I've been getting?

[crowfax]

Correct.

The drive needs to be able to read a bit-for-bit perfect copy of the disc in order to rip it, or you'd end up with gaps in the data which would create an invalid file. The errors your seeing are the drive telling you it can't do that.

It's important to remember that ripping the disc is different to playing it. When playing a disc the drive can skip bits it can't read and carry on, like a needle on a record skipping a groove. You might not be able to see the imperfections but they are there.

This is why you'll ofte, hear people say "it can't be the disc I can watch it perfectly fine". The two are unrelated and thus the ability to play a disc can be ignored when deciding if a disc is in good enough condition to rip.

If the same discs are failing in many drives its the disc. If the same drive is failing with many discs it might be the drive.

[Woodstock]

To amplify what was said, I have three drives available to me - the Bluray drive I use as primary, an original Sony USB/Firewire DVD writer, and a generic DVD R/W drive in another computer. Sometimes the BD drive can't rip a disk, but the Sony sees everything just fine. The difference in laser and optics can make a big difference.

Other times, I have some cleaning (and occasional polishing) to get the disk to rip; Never lend your disks to other people, because they WILL scratch them!