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Ken A.T.
15-07-2002, 12:36 AM
Hi...
If I delete a file on a cd-rw disk is the file still lurking ready for an unerase command, or has it gone to that great folder in the sky...lost forever. Thanks for an answer to this. Cheers...Ken

-=JM=-
15-07-2002, 12:53 AM
it depends on how you *erased* the disc.

If it was a quick format it should still be there ( i have no idea how you would get it though). If it was a full format it would not be there.

boom23
15-07-2002, 02:43 AM
Not too sure if you can recover files from cd's. Hard drives and cd's use different storage technology. HDD uses read/write head, cd-rom uses laser. Maybe someone out there has the solution.

merlin-nz
15-07-2002, 01:07 PM
Hi yah,
This may answer a question for u, found on the site below.

"Full Format, this option takes about 25 to 45 minutes, it verifies the integrity of the CD surface, prepares the CD for data, and writes the UDF file system to the CD. Any data that was on the CD will be completely erased.
Quick Format, this option takes only a few minutes. It writes the DirectCD file system to the CD, but does not verify the physical condition of the CD. Any files that were on the CD will not be accessible, but they are still on the CD:"

http://www.unisa.edu.au/itsupools/news/cd-rw.htm#formatting

cheers merlin ;)

Graham L
15-07-2002, 04:32 PM
If it hasn't been physically erased, there will be a way (not neccesarily easy). Norton's Utilities might be able to do it. If you have (or know someone who has) a Linux box, you could have a look. There are a number of utilities which are capable of picking data off a device --- regardless of file structures, OS nonsense, etc. (e.g. dd is very powerful).

boom23
15-07-2002, 06:52 PM
I doubt norton will do the job. You would need a powerful files recover program

Graham L
15-07-2002, 07:10 PM
I wasn't referring to any sort of file recovery programme (powerful or not); I was saying that it is possible to do a raw data copy and then given time (and some luck), make files out of the readable bits. For example: if you know that a deleted file starts at "sector X of track Y and head Z" on a hard drive, and that it is blah sectors long and not fragmented, you can actually recover it.

A CD file will not be fragmented (I think), so it should not be too hard. But you need a way to do a copy of raw data in a non file-structured way, then massage it. NU used to be able to do this (absolute sector reads, the "/m" option, ... --- I haven't looked at the more modern ones). The filesystem is different, so you need a programme which can handle the fs ... but at the worst, if you had an important text file which was accidentally deleted, you can copy the whole data content (even "deleted" files) of the CD to a HD and do some searching for recognisable text. It's always been much harder with binary (executable, etc)files, and almost impossible with compressed ones.