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I was trying to copy a few image files from my CD and I got

"cyclic redundancy check error"

A lot of my useful photos are not copied. I tried to recover them with several recovery freewares by searching, but, when the software tries to recover the pictures, it gets stuck at the same image [possibly corrupted?].

Is there any free tool to seamlessly recover CD contents?

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If you'd like to look at some tools that are specific for CDs/DVDs, here's a few programs you should check out.

  • IsoPuzzle: Freeware. Reads to an ISO image and maintains a Flag file. The flag file lets the program know which sectors of the disk were successfully read and which weren't. Then you can take the ISO & flag file from system to system, trying different makes/models of optical drives to fill in the blanks.
  • IsoBuster: Shareware. Mostly targeted towards recovering from bad burns, reformatted R/W discs, lost sessions, etc. Allows for using multiple drives to recover data like IsoPuzzle with the Managed image files feature.
  • CDRoller: Shareware. Similar to IsoBuster, though has more non-recovery features, (e.g. burning support, recovery from USB/Flash, etc.).
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There's a few tools you can try in Unix/Linux : dd_rescue, dd_rhelp, and ddrescue. dd_rhelp is a front end to the older dd_rescue. ddrescue is a newer version. You can read about the flavors on wikipedia.

ddrescue is probably the best bet (from the manual):

Example 3: Rescue a CD-ROM in /dev/cdrom.

 ddrescue -n -b2048 /dev/cdrom cdimage logfile
 ddrescue -d -b2048 /dev/cdrom cdimage logfile
   (write cdimage to a blank CD-ROM)

-n does a quick read to recover anything good, -d re-reads the CD to try to get the broken parts.

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The best tool I've found for recovering CDs in Windows is IsoBuster.

It creates an image of your CD and starts reading the sectors, updating the ones it successfully reads, the bad ones get scheduled for the next pass, and the process repeats itself until everything is recovered. You can even take with you the CD image and the CD and do the recovery using a different PC or CD drive (somehow the unreadable sectors are different for different CD drives).

I've managed to recover CDs with such damage I couldn't believe it finally worked (in one case it took 3 days, but I got a bit-by-bit exact copy of the original, as checked by the SHA1 fingerprints.)

A free (and less featured) alternative is IsoPuzzle, which used to be at You might still be able to find a mirror.

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I forgot, the paid version of IsoBuster is needed to recover UDF CDs, if that's not what you need you might be perfectly fine with the free version. – TheNewbie Feb 24 '11 at 19:40
According to the help file: PRO functionality unlocks high end data recovery from UDF CDs (And Image Files). UDF is the File System used by Packet Write Applications such as Direct CD, InCD, Packet CD, DLA, ... . UDF is also used on DVD and the occasional normal CD (next to other File Systems) UDF is the preferred File System to be used with Mount Rainier. – TheNewbie Feb 24 '11 at 19:41

Roadkil's Unstoppable Copier will certainly help you.

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.

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tried it many times does not seem to be useful – Ravisha Oct 19 '10 at 12:43
What is it that doesn't seem useful? Is it coming to a point and hanging there? Please give the details so I can help you better. – Mehper C. Palavuzlar Oct 19 '10 at 13:05
I have few images which cannot be copied. I get the error "cyclic redundancy check error" for those. When i tried to use the tool mentioned it hangs when this file is being copied. I have to close the process – Ravisha Oct 20 '10 at 4:17
more than 5 mins per file?? – Ravisha Oct 20 '10 at 8:40
I tried with several options all in vain. It did copy files but they are not opening in image viewers :(:( anyway thanks for the help though – Ravisha Oct 20 '10 at 11:46

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