Alert re: CM10 on GSIII and SD Card Formatting (With Solution)

**Jonathan I Ezor#IM** · 08-27-2012, 12:58 PM

Just a word of caution for those of you who may be considering swapping the stock GSIII ROM for a recent CM10 build: you may have trouble with your removeable SD card afterwards. Specifically, as I've read in posts , CM10 currently only supports FAT32 formatting, not the exFAT format used for larger SD cards (like my 64 GB microSDHC card). As a result, after installing CM10 and booting your GSIII, you may get an error message that says your card cannot be read and needs to be formatted. Worse still, you might get the same error message if you pop the card and put it into your computer to check it out.

DO NOT REFORMAT IT UNLESS YOU HAVE PREVIOUSLY BACKED UP ITS DATA. YOU WILL LOSE EVERYTHING ON IT, AND IT ISN'T NECESSARY TO DO SO.

Instead, you can follow the instructions in the above-linked post, or (if you're running a Windows machine) launch a command prompt (by running CMD), and use the good old DOS CHKDSK utility to fix the file system. For example, if your computer shows the "unreadable" SD card as drive letter F:, launch the command prompt and type:

"chkdsk f: /r"

The "/r" option tells Windows to repair any errors it finds. It may or may not be necessary, and you may or may not see the process end. In my case, after CHKDSK appeared to freeze, I closed the window and checked Windows Explorer. Sure enough, my microSDHC card was fully readable, with its files intact. *Whew.* Even better, once I restored my GSIII to the stock ROM, the fixed card worked fine.

Hope this helps. {Jonathan}

**resu_ruot** · 09-02-2012, 01:49 AM

Thank you. This exact thing happened to me and your solution helped.

**resu_ruot** · 09-02-2012, 02:18 AM

Ok so maybe I was a little premature in saying that it fixed the problem. When I checked the card on my computer it wouldn't read it initially, but then I followed your steps and everything seemed to work. Once I placed the card back in the phone I get the same errors: Damaged SD Card. Any idea what I can do? I've tried formatting the card on the phone and it's not working either. The process seems to stick at "unmounting SD card".

**resu_ruot** · 09-03-2012, 01:08 AM

If anyone is still interested I ended up reformatting my micro sd card to fat32. That was the only thing that seemed to work.

**Stealthieone** · 09-05-2012, 12:52 AM

Originally Posted by pablomoca

If anyone is still interested I ended up reformatting my micro sd card to fat32. That was the only thing that seemed to work.

So now your gs3 does not say its a damaged card?

**PJnc284** · 09-05-2012, 07:20 AM

Originally Posted by pablomoca

If anyone is still interested I ended up reformatting my micro sd card to fat32. That was the only thing that seemed to work.

yeah, if you're using CM10, you HAVE to format it as FAT32. That's the only way it's going to work as the sdcard is corrupted on boot if it's exFAT.

**Stealthieone** · 09-05-2012, 12:31 PM

Originally Posted by PJnc284

yeah, if you're using CM10, you HAVE to format it as FAT32. That's the only way it's going to work as the sdcard is corrupted on boot if it's exFAT.

How do you do that on Windows 7 pc.. When I try to format I only get the exFAT option

Sent from my SAMSUNG-SGH-I747 using Tapatalk 2

**jaj6503** · 09-05-2012, 01:12 PM

Isn't this mentioned in the CM10 OP?

Sent from my SCH-I535 using Android Central Forums

**jaj6503** · 09-05-2012, 01:13 PM

Originally Posted by Stealthieone

How do you do that on Windows 7 pc.. When I try to format I only get the exFAT option

Sent from my SAMSUNG-SGH-I747 using Tapatalk 2

Google search/download/use the free app SDFormatter. Just don't accidently select your hard drive when using it.

Sent from my SCH-I535 using Android Central Forums

**Stealthieone** · 09-05-2012, 01:55 PM

Originally Posted by jaj6503

Google search/download/use the free app SDFormatter. Just don't accidently select your hard drive when using it.

Sent from my SCH-I535 using Android Central Forums

Lol I already did that and that also formatted as exFAT. I've also tried swissknife and a couple others. Seems like no matter what I do, it's exFAT. Also sdformatter doesn't even let u select the format

Sent from my SAMSUNG-SGH-I747 using Tapatalk 2

**Stealthieone** · 09-05-2012, 02:14 PM

Btw if I want to go back to stock of.. Do I just do a factory reset?

ReseySent from my SAMSUNG-SGH-I747 using Tapatalk 2

**NotJustAPhone** · 09-05-2012, 03:21 PM

Originally Posted by Stealthieone

Lol I already did that and that also formatted as exFAT. I've also tried swissknife and a couple others. Seems like no matter what I do, it's exFAT. Also sdformatter doesn't even let u select the format

Sent from my SAMSUNG-SGH-I747 using Tapatalk 2

Search for a tool called GUIFormat. That's what I used to format my 64 gig card as FAT32.

Sent from my SGSIII

**jaj6503** · 09-05-2012, 08:21 PM

Originally Posted by Stealthieone

Lol I already did that and that also formatted as exFAT. I've also tried swissknife and a couple others. Seems like no matter what I do, it's exFAT. Also sdformatter doesn't even let u select the format

Sent from my SAMSUNG-SGH-I747 using Tapatalk 2

Lol just trying to help you.

Sent from my SCH-I535 using Android Central Forums