Lee269,
A bit late on this as I have been away on holiday.
I am no expert on these matters but have been concerned about the durability of CD-R/RW and/or DVD-R/RW backups ever since I started the process of ripping my own LP's and cassettes. Eventually I would like to save the space taken up by these and dispose of them but having heard so many horror stories of unrecoverable files from these media types I don't know if I dare risk it!
One place for good advise on this sort of thing, although quite often technically over my head, is the mail list at:
http://groups.yahoo.com/group/advanced_cdr I can't remember the reasoning now but when I started the process I decided to use DVD-R as my permanent backup. I use DVD-RW on a temporary basis whilst I am getting the tags rights.
I was using Roxio's latest software to write the disks and had transferred about a hundred albums to DVD-R when I had a problem copying files from a DVD-RW, a new blank created only weeks before, to a DVD-R. I started to feel concerned and tried copying back to HD all the DVD-R's I had created and found quite a number of uncopyable files. Panic then set in - what if I had disposed of the originals and the file in MC became corrupted? Whilst, as had been said, this is not the end of the world it is not what one would like to happen either.
Through the above Yahoo Group I gleaned the following:
1. CD burning software such as Roxio and Nero and, no doubt, others does not verify that what it has sent to the burner has been successfully written. Don't know what MC does. This, of course, make for high writing speeds but what good is a disk written in 10 minutes if you can't get the data back.
2. Because of the small number of disc manufactures, who obviously sell to the 'Brand Names', as well as the 'unbranded' market you could get a bad batch from a 'Brand Name', selling for many times as much as the same product in 'unbranded' form.
3. If the burning software does not verify the writing process, as mentioned in 1. above, you will not know until you try to use it that you have a problem as happened to me.
I also found, via this group, a couple of pieces of software from:
http://www.infinadyne.com CD/DVD Diagnostic - "The #1 data recovery software! Recovers lost data, photos, files, music and more from CDs and DVDs. Now supports DVD recorder discs! More tools, more features and more capable than the competition."
AccuBurn–R - "Accurately burns CD data. Guaranteed! No more data loss, user errors, or ruined discs! NOW SUPPORTS DVD's!"
The first managed, to my relief, to recover all but two of the files that Windows could not copy. I have since used the second to do all my burning, as it does verify after it writes and reports any problems it finds with the media.
As I have said I am no expert but I now feel a bit more confident in my DVD backups. However, as nothing is perfect I am also making another backup to an external HD.
As you know the use of external HD’s for backup is popular with the members here and these can, and do, of course, fail. If you get a total failure at least you can replace it and recopy the files from the HD being used by MC. More of a concern is slow unseen problems. As we, obviously, play our music at random intervals it could be some time before we notice a problem with the MC copy of a track and go to our HD backup to find that is also is bad.
In considering this I found a program called “SpinRite” from
http://www.grc.com. This basically does non-destructive testing, at various levels, of the HD surface to warn of any actual or imminent problems and may be of interest for general use as well as specifically for MC. By the way they are also renown for their free “Sheilds Up!” testing of your internet security.
I hope this information/experiences may be of some use.
David