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I have loads of CDs and DVDs in my archive mostly containing programs, photos and videos. Some of them are either damaged from the edges or scratched.
How can I recover my data on those old disks? Are there any physical implementations before using a recovery software?
What kind of protection methods do you recommend to extend the lifetime of disks?
Mehper C. Palavuzlar
Posted 2009-10-20T14:43:13.333
Reputation: 51 093
3
Clean the disks very carefully, use a light polish like Mr Sheen on scratches or I have used car polish on deeper ones.
Clean off well before use and use good quality reader.
As per WilHil comment Magic iso is good for mounting cd's etc http://www.magiciso.com/
Scott Belton
Posted 2009-10-20T14:43:13.333
Reputation: 71
1
If the scratches are deep, you can always take it to a professional who will use fluids and special heads that can buff it out and hopefully fix.
Next, convert all the disks to ISO's, use a program that does not stop on errors (trying to find best one and I will edit) and this should give you an image file on your machine that you can mount using any virtual cd program. A lot of the files may be currupt and not readable, but as long as cd was somewhat repaired, you should be able to get to the majority of your files.
William Hilsum
Posted 2009-10-20T14:43:13.333
Reputation: 111 572
A program like ddrescue is just what the doctor ordered. Perhaps when you make your edit you could include information about ddrescue. – eleven81 – 2010-01-12T13:35:55.650
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If you insist on burning to optical media, I recommend using a tool like QuickPar to generate parity archives. With carefully chosen settings, this will allow you to recover data even if chunks of your disk are bad. It can take quite a lot of CPU power to create the PAR2 files, however.
When I have burnt disks for archival purposes, I have tended to go with fairly small files (~100 MB each), and enough recovery to rebuild even if three or more of the files on each DVD are bad. This has worked well for me in the past, but it is fairly time-consuming. Also, QuickPar has issues when you are dealing with sufficiently large files. I do not recall if the limit was 2 GB or 4 GB, but regardless, pretty small in this day and age.
ChrisInEdmonton
Posted 2009-10-20T14:43:13.333
Reputation: 8 110
1
I recommend using dvdisaster to add recovery record into the ISO image before burning it. DVDs that have been "enhanced" with dvdisaster can withstand multiple sector errors and still be recovered. Also you can verify that disk with the application. Only drawbacks are that you lose about 5-15% of storage capacity per disc depending how much you add recovery info and you need to create an ISO image first. Fortunately you can easily create a script that will enhance the ISO and then burn it automatically, so the inconvenience is minimal. And you sleep better as you know the media will still be readable after couple years.
Raynet
Posted 2009-10-20T14:43:13.333
Reputation: 674
-1 Guy is asking about already burned disks. – kinokijuf – 2012-03-10T11:32:12.977
@kinokijuf "What kind of protection methods do you recommend to extend the lifetime of disks?" was also part of his question. This is a valid answer. – Bob – 2012-03-10T12:10:36.090
@Bob Discs, not images. – kinokijuf – 2012-03-10T12:13:37.480
@kinokijuf What I understand from his description and the linked program ("dvdisaster stores data on CD/DVD/BD in a way that it is fully recoverable even after some read errors have developed") is they take images as input and burn to a disk as output. There is the extra step of generating the images first, but the end result is a disk that has a higher chance of recovering from errors, that naturally develop as they age. Therefore the lifetime is extended. In fact, that is what ChrisInEdmonton's answer suggests. – Bob – 2012-03-10T12:18:03.320
@Bob The error are still there, operating systems contain no support for such things and you need to use their program to recover data. – kinokijuf – 2012-03-10T12:38:01.460
@kinokijuf I'm curious if you are just trying to find faults, yes you are entitled to downvote without a reason, but you have now tried explaining it through "already burned disks", "discs, not images" AND "operating systems contain no support". The question did not ask for a method built in to the OS, and this would definitely work for archival purposes. – Bob – 2012-03-10T13:02:15.433
@Bob but not for preservation purposes. – kinokijuf – 2012-03-10T13:04:43.767
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Roadkil's Unstoppable Copier recovers files from disks with physical damage. Allows you to copy files from disks with problems such as bad sectors, scratches or that just give errors when reading data. The program will attempt to recover every readable piece of a file and put the pieces together. Using this method most types of files can be made useable even if some parts of the file were not recoverable in the end.
Unstoppable Copier is freeware and portable.
I tried Unstoppable Copier it too got hanged during copy – Ravisha – 2010-10-17T12:12:05.950
Never tried, but if this works, amazing! Must try on some of my damaged cd's... They were never important enough for me to take to a pro. – William Hilsum – 2009-10-20T14:56:57.193
Thanks, Wil and Scott (+1). I never tried this but erstwhile I've heard that keeping CDs in refrigerator for a while (before recovery process) increases probability of data recovery. I really wonder the logic behind it... – Mehper C. Palavuzlar – 2009-10-20T18:10:33.687