Corrupt SDHC card? Way to fix & test?

[NAC]

I think I corrupted my SDHC card by interrupting a download. Some newer files since then had problems. Is there a way to low level format the card via a USB card reader and therefore not use any bad sections? Is there software to test it thoroughly?

 

[rsutoratosu]

like to know also.. one of my card doesn't work on a sd reader on a particular pc but works on everything else.. i figure if i low level format it, it might work

 

[Cerb]

1. Plug it into a Windows PC.
2. Start->programs->accessories->command prompt
3. If on Vista or newer, right-click and choose to runs as Administrator. If on XP, just run it.
4. Find the drive letter. I'm using G.
5.

chkdsk G: /r

FAT32 will corrupt at the drop of a hat. Let chkdsk scan and fix it, and try to not rudely unmount it, whenever possible.

If you need to reformat it, use Panasonic's SDFormatter, if it supports your card, for best performance. It doesn't support any recent Samsung I've bought, FI, but, I also haven't had any issues with those cards.

like to know also.. one of my card doesn't work on a sd reader on a particular pc but works on everything else.. i figure if i low level format it, it might work

You can't, typically. You can only do high-level work on them. They appear as a modern MBR HDD. SDFormatter can do magic with some old chips it directly supports, but today, it's much more common that the most you can do is repartition and reformat it (make sure to partition it with the same offsets as it had from the factory, if you intend to go that far).

 

[NAC]

Thanks Cerb, I'll give it a shot.

 

[razel]

You don't want the /r in there. /r searches for bad sectors and trys to remap as much info as it can read. I am not sure if that remap is on the filesystem level or physical disk SMART level. Since most SD cards aren't 'smart' enough to remap when a bad sector is found, I get a feeling it'll be in the file system level. Regardless, at that point, it's too late.

You'll just want /f (fix) or /x (force dismount, then fix). I prefer /x.

 

[Cerb]

You don't want the /r in there. /r searches for bad sectors and trys to remap as much info as it need. Most SD cards aren't 'smart' enough to remap when a bad sector is found, so chkdsk will try to do it. However at that point, it's too late.

/f/p, then, if that worries you. /r is normally just to not need to remember other flags.

I generally assume there won't be enough of those blocks to worry about, and if any got made, there are GBs to spare, anyway. If chkdsk comes upon a bad sector, there's nothing it can really do, but mark it. Proper remapping is a feature that harkens back to the days of ATA-33 and before.

You'll just want /f (fix) or /x (force dismount, then fix). I prefer /x.

/x will only make chkdsk complain to you.

 

[NAC]

chkdisk did not find any errors on the SD card. Note that it was blank when I tested - I had just formatted it. I had used SDformat - I could only do a quick format.

I tried an app called H2testw - see link below. It found errors - the error log is also below. I guess I will throw out the card. Even if I could fix it - I'd hate to lose more data in the future. Thoughts?


Link to H2testw
http://translate.google.ca/translat...2&ct=result&prev=/search?q=H2testw&hl=en&sa=G


Output from H2testw:
The media is likely to be defective.
5.6 GByte OK (11820992 sectors)
9.5 GByte DATA LOST (19970112 sectors)
Details:0 KByte overwritten (0 sectors)
0 KByte slightly changed (< 8 bit/sector, 0 sectors)
9.5 GByte corrupted (19970112 sectors)
0 KByte aliased memory (0 sectors)
First error at offset: 0x0000000168bf8000
Expected: 0x0000000168bf8000
Found: 0x0000000000000000
H2testw version 1.3
Writing speed: 13.8 MByte/s
Reading speed: 13.9 MByte/s
H2testw v1.4

 

[NAC]

For reference - this was the output from chkdsk:


C:\Windows\system32>chkdsk J: /r
The type of the file system is FAT32.
Volume CANON created 5/5/2013 12:53 PM
Volume Serial Number is 1469-0C56
Windows is verifying files and folders...
File and folder verification is complete.
Windows is verifying free space...
Free space verification is complete.
Windows has checked the file system and found no problems.
15,898,624 KB total disk space.
32 KB in 1 hidden files.
256 KB in 8 folders.
96 KB in 3 files.
15,898,208 KB are available.

32,768 bytes in each allocation unit.
496,832 total allocation units on disk.
496,819 allocation units available on disk.

C:\Windows\system32>

 

[AkumaX]

https://www.sdcard.org/downloads/formatter_3/

 

[rsutoratosu]

Nice, did not know such thing existed

 

[Shmee]

Um, this thread is like 5 years old. Closing.