Why are 90% of my data dvds unreadable?!

Question

Level 1

40 points

Why are 90% of my data dvds unreadable?!

I'm about to receive my Mac Pro 3ghz, so i'm tying up loose ends on my G4 now. Namely, I've been trying to load all the stuff I previously stored on DVD's, so all my old Cubase songs will be sitting on the G4, waiting for me if i ever decide to work on them.

Incredibly, 90% of the dvd's just churn for around a minute, then get spat out without ever being recognized by the computer! Why is this? I only burned them one year ago.

The other surprising thing is that i have cd-roms from 5 years ago which loaded just fine. The dvds were made by big companies. Memorex, TDK, etc.

When I originally burned them, i always verified that they were burned successfully. They just turned rotten in a year.
I certainly don't remember a warning label on the package stating that the data won't last more than one year.

Does anyone know if there's a way to retrieve the data? Is there some setting on the computer to help?
Is there a chance that the Mac Pro will be able to read them if the G4 can't?

Is there a more reliable format? Is +R better than -R ?

At this point, i don't think i'll ever use dvd's as a backup method again, unless i learn how to do it reliably.

PowerMac G4 dual 1.25 ghz Mac OS X (10.4.7) about to receive Mac Pro 3ghz, 8GB RAM, 3 x 10,000rpm raptor drives, 1 x 250 GB Apple drive

Posted on Sep 20, 2006 3:41 PM

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Answer 1

Cindy

Level 2

240 points

Sep 20, 2006 4:20 PM in response to man 'O tunes

Thats scarey! I would like to know the answer to that too. I have tons of burned DVD's

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Answer 2

man 'O tunes Author

Level 1

40 points

Sep 20, 2006 7:18 PM in response to Cindy

if i were you, i'd load all your important dvds back onto the computer till yer able to buy a backup external drive. don't make the same mistake i did.

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Answer 3

Sep 20, 2006 7:47 PM in response to man 'O tunes

Here are a few Apple Knowledge base documents that might helps…

Troubleshooting a CD-ROM or DVD-ROM Disc That Does Not Appear on the Desktop…

http://docs.info.apple.com/article.html?artnum=58382

… Factors that affect writing to or reading from optical media…

http://docs.info.apple.com/article.html?artnum=25402

… and, while specific to slot loading mechanisms it may help, MacBook Pro, MacBook, PowerBook G4, iBook G4: Troubleshooting the slot load disc drive…

http://docs.info.apple.com/article.html?artnum=88275

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Answer 4

ArcticMac

Level 2

380 points

Sep 20, 2006 10:12 PM in response to man 'O tunes

at my school we've got some eMacs, and I've known them to occasionally just reject DVDs for no particular reason. Doesn't happen with CDs, but... Sometimes it'll work, sometimes not (I think). You might try in a different computer, or after restarting yours. Also, you might try in OpenFirmware...
hold apple-option-o-f on boot then type:

eject-cd
**insert disk in drive now **
eject-cd
dir cd:,\

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Answer 5

Hworld

Level 1

55 points

Sep 20, 2006 11:22 PM in response to man 'O tunes

FYI, nowadays, even the big name companies outsource their DVD manufacturing so quality can be hit or miss.

Another factor is the source DVD burner. From my own experience, older writers coupled with dodgy blank media burned discs that often time could not be read in anything else except the drive I burned it on. The original Pioneer DVR-103 "Superdrive" in my QS G4 was famous for doing this and when using certain brands of blank media (like Ritek and Prodisc for example), could only be read on that drive. If I used something expensive (like authentic Japanese made Taiyo Yuden's), then I stood a better chance of having that disc readable on something else.

Also, some Memorex DVD-R's were notorious for burning and verifying okay only to be unreadable a few months later. I wish I still had the media ID code for those particular bad blanks.

Recently, I've settled on Verbatim's and have had excellent results with the following (especially the 8x silver DataLife Plus) in terms of burnability and ability to be read on a wide variety of computer readers and consumer DVD players. I've burnt over a thousand of these (using a Pioneer DVR-109) for the past few years and the oldest ones are still readable. The manufacturer ID of these start with MCC (Mitsubishi Chemical).

http://www.amazon.com/Verbatim-Single-sided-DVD-R-Spindle-Discs/dp/B0009YJXMI
http://www.amazon.com/Verbatim-Silver-DataLife-DVD-R-Spindle/dp/B0002IQ1F8

Mac OS X (10.4.7)

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Answer 6

man 'O tunes Author

Level 1

40 points

Sep 21, 2006 3:49 AM in response to infinite vortex

Thanks so much for the help Ned. Still trying, but that article at least gave me some ideas to try. At the moment, i can't find the firmware update for a G4 Mirrored drive. They keep saying that no update is needed. The thing is, i fear the firmware might be corrupted. It's not that i don't have the right version. i just want to reinstall it.

Oh well. I'll try more ideas tomorrow.

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Answer 7

Sep 21, 2006 5:21 AM in response to man 'O tunes

This may not help now, but I went through this - Data DVD's did not show up on the desktop and even when they did, the transfer was iffy.

I then burned data on the dvd at the slowest rate x 1, in most cases instead of x4 or 8 .... this worked. All the dvd's burned at a very slow rate were fine.

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