File recovery software SD card

[PatrickMcCluskey]

It has been a long time since I have visited this forum due to circumstance and hoppe to be visiting more regularly now.
I have been asked by a friend to try and recover some holiday pics from her SD card and am looking for some good free software, I'm not sure if she has formatted or not but think she has. the thing is when putting the card in to my card reader it is not being picked up by the PC.
Admittedly it is a cheap TEVION SD card but never the less it has her precious holiday memories on it.
What is the best free software to download and use, or will this not make a difference as the card is not being picked up by my PC.

Hi Patrick
If you can save a copy of as many files as you can into the internal memory of the camera and transfer them to a new (formatted) card - Or tranfer them directly into the PC/Mac - I lost loads when a card failed on me! So I hope luck is on your side - (my card was formatted and then reformatted again by the PC without a notice or request box!! wiping it clean)

Regards
Andy

[Robster]

I have not found any recovery software works and have now tried three versions and the only thing they have managed to do is recover files that had been deleted but not after formatting and could not recover corrupt files.
Out of all the shops I asked only one shop gave what I belive to be the honest answer THEY DO NOT WORK AND DONT WAIST YOUR MONEY.
I wish and hope there is a programe that does recover corrupt files out there somewhere!

[NormanLaw]

I'm sorry to say that most recovery programs are designed to retrieve files that have been deleted or after the card has been formatted. I don't think there's much to be done if files are otherwise damaged or the card is corrupt.

You could try the card in some different card readers, they may have more luck.

[Forseti]

Formatting builds or rebuilds the FAT (File Allocation Table) but does not physically delete images although the process of formatting might overwrite some image files. As to why the PC won't recognised the card is another matter for which hopefully someone with more knowledge in the area of computers might be able to help. In the meanwhile I would suggest trying the card in another computer or even in another PC. It could of course be the case that your PC card reader is not capable of reading SD cards especially the high capacity type which is something that does pop up on the forums from time to time.

Assuming that you get the card to be recognised on another computer (especially one that you know can read SD/SDHC cards then you might want to run Zero Assumption on it. This is probably one of the best pieces of data recovery applications available and what's more it's freeware.

http://www.z-a-recovery.com/

[chris-p]

Originally Posted by Robster

I have not found any recovery software works and have now tried three versions and the only thing they have managed to do is recover files that had been deleted but not after formatting and could not recover corrupt files.
Out of all the shops I asked only one shop gave what I belive to be the honest answer THEY DO NOT WORK AND DONT WAIST YOUR MONEY.
I wish and hope there is a programe that does recover corrupt files out there somewhere!

As has been said already, file recovery programs are not capable of recovering corrupted data, only "deleted" data. Corruption is quite a different issue. If the data of the file is truncated, shifted or otherwise moved/lost you won't get it back as the FAT or NTFS tables won't have been updated.

[OldBoy]

Originally Posted by PatrickMcCluskey

It has been a long time since I have visited this forum due to circumstance and hoppe to be visiting more regularly now.
I have been asked by a friend to try and recover some holiday pics from her SD card and am looking for some good free software, I'm not sure if she has formatted or not but think she has. the thing is when putting the card in to my card reader it is not being picked up by the PC.
Admittedly it is a cheap TEVION SD card but never the less it has her precious holiday memories on it.
What is the best free software to download and use, or will this not make a difference as the card is not being picked up by my PC.

If you can't see the card in your PC then it could be a duff card or you need to reset your SD card reader. Sometimes when you use a card slot and remove it whilst the PC is switch on, without using the Remove Hardware option, then Windows thinks it still there, so when you put another card in there it can't see it. Select the Safely Remove Hardware option on your Taskbar and double click it, then from the Window that opens, highlight the one for the SD card, and click stop. Now reboot your computer and it should see the card.

If it's a duff card then you need to find a recovey specialist company to recover the data but may cost around £200. Do a internet search for a disk/data recovery company.

[OldBoy]

Originally Posted by Forseti

Formatting builds or rebuilds the FAT (File Allocation Table) but does not physically delete images although the process of formatting might overwrite some image files. As to why the PC won't recognised the card is another matter for which hopefully someone with more knowledge in the area of computers might be able to help. In the meanwhile I would suggest trying the card in another computer or even in another PC. It could of course be the case that your PC card reader is not capable of reading SD cards especially the high capacity type which is something that does pop up on the forums from time to time.

Assuming that you get the card to be recognised on another computer (especially one that you know can read SD/SDHC cards then you might want to run Zero Assumption on it. This is probably one of the best pieces of data recovery applications available and what's more it's freeware.

http://www.z-a-recovery.com/

There are two types of formatting. One is high level which just deletes the Fat file and doesn't affect the infomation stored on the disk. It's what the camera uses when you select format in camera. The other is low level, which you have to select on the PC and will remove all the infomation on a card or disk. In the second case no recovery software will recover it as the files have been removed. In this case a recovery specialist company may be able to recover it but it could cost £1,000s.

The point you make about SDHC is good as most older PC/Card readers won't be able to read this new format, so it's worth trying in a SDHC reader.

[PatrickMcCluskey]

Thanks all,
Thanks for the replies, I downloaded Zero Assumption and got all the files, but most of them I cannot open.
When I try to open them I am told, this file may be damaged THE FILE MAY BE TRUNCATED OR INCOMPLETE, ITS AS IF THERE HAS BEEN A GREY SHEET PUT OVER 90% OF THE IMAGE, FROM THE BOTTOM UP.
I wonder if most of this damage has happened when trying to open these files using stellar phoenix, as this programme allows you to view the files but wants you to pay around 70$ first ?

[chris-p]

This damage is the corruption.

The way files work is a bit complicated but I'll try to explain. Imagine your hard drive as a filing cabinet with several drawers and loads of individual scraps of paper in every draw. Each scrap of paper is a bit. A file is made up of bits. Now you'd think that the bits would be stored next to eachother in a sensible and organised way but they're not. They are scattered throughout the filing cabinet.

So... you want to open a photo? What you need to do is find thousands and thousands of specific bits of paper in all the drawers of the cabinet all at once and then putting them together in the right order. To do this you have an indexing system. This system tells you exactly where every single scrap is so you can find them. If you lost part (or all) of that index you'd never be able to find all the right scraps. Or if you lost some of the scraps of paper you would never have a while file. This is what happens when files corrupt.

What is happening is that the PC has been able to locate the first bits of data but then either a bit is missing or the index is damaged and it can't go any further. It knows the dimensions of the image (and that the file is an image) because that information is stored in the first bits but when it runs out of info it just fills the rest in grey as it can't find any data.

When you format a disk (or card) you don't actually remove the files, just the indexes so you can't put the files back together. Then, over time, the scraps are re-used and over written. When you try to recover deleted or formatted files you're actually trying to restore the index and the links between the bits. But if some of the bits have been overwritten already or you can't reconstitute the indexing tables properly you won't get the whole file. Only parts of it.

Edit: For clarity the "indexes" I referred to here are the NTFS or FAT32 tables I referred to in my earlier post