Mac Forum / General / Hardware / November 2006

So your drive is working fine with all other CDs and this is the only
one that's problematic?

are you sure you haven't pidgeon holed here?
My outsider perspective from reading the thread:
You say:  "drive seems to read the directory and says that that
directory is blank"

know what sticks out to me?: SEEMS TO...SEEMS TO...SEEMS TO

If it thinks it reading it, but it's not, well, ah, that /IS/ a drive
problem.
This is just my logic, not a hands on experience with your condition.

my $.02 comment,
GW

You're not using a crappy brand of blank CD, such a Memorex, are you?

There's a big difference between different brands of blank CD; each
manufacturer uses a proprietary formulation of dyes in the disc. I have
seen some brands (most notably Memorex) work fine in some computers or
some brands of CD player, but not others. For example, I have three
working Macs right now; one of them will not "see" Memorex blanks at
all, though it works just fine with other blanks.

The same is true of audio players as well. Memorex CDs work in my Sony
CD player and in my car stereo, but are not "seen" at all in my friend's
Sony CD changer or in her car stereo.

The most likely explanation is that your drive is not detecting that any
data was written to the disc - it isn't picking up a strong enough
signal from the burned data to be able to distinguish it from unburned
data.

This will be due to some combination of the optical properties of the
dye used on that particular brand of CD-R, the sensitivity of your
drive, and the degree to which the dye was ablated by the drive which
burned the disc.

Try a different brand of media. My personal preference is for Verbatim
Datalife Plus (dark blue tint) as I've had no problems with it in any
drive I've tried (except where the drive itself was faulty).

You should also try a CD lens cleaner in your drive, as it might be
verging on not being able to read CD-R media due to dirt on the lens,
but is still able to read a pressed CD or CD-ROM.

Dave-

Yesterday I came across some old archive CDs I had burned about six
years ago.  They were bargain CDs with no brand on them.  Some are
developing a quarter inch or so brown stain along the edges.

I decided it would be a good idea to back them up.  However, most have
some files that can't be read depending on which drive I use to read
them.  Some are giving the "blank disc, do you want to format?" message
in one drive or the other.

Realizing that my bargain CDs were mostly lost, I played along with one
and told it to mount it on the desktop.  I copied a single file to it,
and was prompted to burn it when ejecting.  The burn was a failure, and
now the CD can't be read on any drive.  My experiment ruined whatever
usefulness that might have remained.

My next experiment will be to see if "Data Rescue II" will save any more
of the old files.

Fred