How badly does not ejecting an SD card screw it up?

[PhotoGramly]

So I pulled my SD card out of a laptop without ejecting it (in desperation) which wiped the files and seems to have screwed up some other photos I transferred using that same card, is that something you can come back from? I'll be using my other card for everything important from now on, but do you think there are any measures that could save the original card (like formatting it in the camera)?

 

[SCraig]

Any time you pull a media device out without properly dismounting it you run the risk of corrupting whatever happens to be in the process of being written at the time. Since there is frequently a lot of writing and reading to the file allocation table (which tells the computer what segments belong to what file). If that file gets corrupted many or all of the files may become unreadable. They are still there but the computer doesn't know where and it can't read the FAT.

Generally, unless there is something physically wrong with the device, that is ALL that happens though. Reformatting the device will zero-out the FAT and tell the computer that there are no files on the device (even though the data is still there) and all will be good again other than all files being effectively gone.

 

[dunfly]

Before I did anything, I would run a recovery program on it. You may be able to recover a lot of the lost files. I use the free version of Recuva. It has saved my ass a number of times.
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