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I'm running CM 10.1 (based on Android 4.2.1) on a Galaxy S III i9300. I'running CWM-based recovery v

I'm dealing with a conflict with my Sandisk microsd 32 gb card. When I format my sdcard to fat32 and run recovery mode, the phone does not read the sd card. However, if I change the format to exfat, the phone reads the sdcard in recovery, but then it won't mount the sdcard when I reboot the phone. I get an "sd card damaged" error.

Likewise, when I connect phone to PC via USB my PC does not detect the card within the phone; I have to use an sdcard adapter and insert it in my PC to access it.

When I use CM updater, the system reboots and gives me the following error message under "verifying update package...":

E: failed to open /sdcard/0/cmupdater/ (No such file directory) E: Signature verification failed, Installation aborted

If I then pull the update from, I can access it from external storage, but I get this error message when I try to install it:

E: failed to verify whole-file signature

E: Signature verification failed

Everything is solved by converting to fat32--PC reads card, phone mounts card--except the issue of installing updates or flashing ROMs, kernels, etc in Recovery. This means that when I want to add media to my card I have to format it to fat32 and then re-format it to exfat when I want to access it in Recovery to do things like install updates to CM 10.

Am I missing something? Is there a way around this?

I read a post on XDA, though I can't remember where, that said that the size of the card (specifically, if it is greater or less than 32 gb) affects what format the S III will read it in. Is it true?

share|improve this question
CWM shouldn't be verifying signatures, are you sure you're running CWM? – Matthew Read Jan 16 '13 at 17:15
I just noticed that when I reboot in Recovery Mode, I enter into CWM recovery; however, when I use CyanogenMod updater and am prompted to reboot into recovery to install updates, I reboot into Android Recovery. Any idea why this happens? – tylerharms Jan 17 '13 at 10:33
I'm not sure. However you could try manually rebooting and flashing that zip, since you know the path. – Matthew Read Jan 17 '13 at 15:55

Have you tried considering a mutli-partition SD card? There are a few tools like SDMinste and Partition Wizard to help you create a dual partition setup on your SD card. You could create a small partition to store all your ROMs and updates, and a bigger partition for your user data.

However, there's a slight problem wherein Windows will only recognize the first partition. Refer this well written guide on XDA for a workaround.

share|improve this answer
I'll look into this and let you know. – tylerharms Jan 12 '13 at 13:13

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