Update On 32GB CF Card Errors
I received a replacement SanDisk Extreme 32GB 120MB/s UDMA7 card from B&H and it exhibits 11 Fatal Read Errors at the exact same LBN locations as the first card using Flash Drive Test Utility v1.14. It appears this test utility is not compatible with 32GB UDMA7 cards. I sent an email to SanDisk Tech Support and received two responses:
I would like to inform you that the software that you are using is not a suggested software to test our cards so I would recommend you to us the card in the device that you have. If you face any issues while you are using this card on your camera you can contact us back again and we will surely go ahead and assist you. You can also revert back to this email for further assistance or contact us back again for further assistance.
What software do you recommend that I can use to test this card?
I understand your concern regarding the card showing errors however would like to inform you that we do not have any suggested software to test our cards and if you face any issues while using this card on your camera then please contact us back again with your incident ID1735950 or revert back to this email for further assistance and we would be glad to replace the card for you.
Although it's good to know SanDisk will replace defective cards that won't help end-users recover corrupted files on the card!
A search on Google pulls up scant few Flash Memory test diagnostics, freeware or paid. I did find one called 'CheckFlash 1.16' written by a programmer based in the Ukraine. It is fast and uses two data patterns (Hex5, HexA) to insure all memory cells can be written to both 1 and 0 and read back correctly. The Flash Drive Test Utility 1.14 and others write a single test pattern and then read back and compare the data. This is fine to check the actually memory size to find "fake" cards and USB drives, but won't insure data integrity.
There is only a Windows version, but it runs fine on my Windows 7 64bit system. The SanDisk Extreme 32GB 120MB/s UDMA7 card passed with no issues! Select your memory card in the dropdown 'Drive' selector and then use the settings as in the below screenshot. THIS WILL OVERWRITE ALL DATA, so first backup any files on the card to your hardrive.
The 'Small pattern test' is alternating 1010 data followed by 0101 data on the 2nd pass. This insures insure all memory cells on the card are functioning properly. The 'Full pattern set' is much more extensive and will take quite a long time to run on large cards. If you have a card that has issues and it passes the 'Small pattern test' then you might want to run the 'Full pattern test' it before tossing the card in the garbage. If it passes both tests you probably have other issues.
Use a good high-speed card reader, preferably USB3 or FireWire. You will need to Format the card when you replace it in the camera.
Message was edited by: trshaner Corrected 0101 data test pattern.