[Steven Preston]

After speaking with a tech at a camera store I think the conclusion is slow, lower end cards are causing the problem with the powerful 7d system. As San Disk Ultra are “B Memory” as he described it, and the lower end of the San Disk Ultra, Extreme, & Extreme Pro series. (other cards he described as using “A memory”)

With the 7ds Dual DIGIC 4 Processor, it writes much faster than the 5d, this may explain why cards the worked in 5d mkII crash when used in the 7d. For me, when the card “crashed” and read “busy” I pulled the battery to reset, this corrupted the card because the files were not finished writing, then when I put my new card there was still data in the buffer and the camera tried to write that to the new card, therefor corrupting that card as well.
This is how it was explained to me by a reputable camera store employee.

Long story short, im dropping San Disk 30mb and ponying up for the next level and getting off San Disk completely, Delkin Pro UDMA 16gig.
Hope this helps anyone else out there.

And as for the corrupted data, I think its gone for good.
Good luck.

[Steven Preston]

Interesting, I will test with other cards.
As for reformatting every time I do that already, as after I dl a card, I clear/format in camera.

Any advice on recovering files? Like I said it appears data is there, just cant access it, Data Rescue 3 no help