# [SOLVED] FAT32 not recognised

## marinheiro

I have just reinstalled gentoo on an old macbook. Almost everything is working fine except that I can't read usb devices that were fine before (in particular, camera and kindle). I get exactly the same symptoms from both:

lsusb: 

```
Bus 001 Device 010: ID 1949:0004 Lab126 Amazon Kindle 3
```

dmesg:

```
 [ 6176.719419] scsi 6:0:0:0: Direct-Access     Kindle   Internal Storage 0100 PQ: 0 ANSI: 2

[ 6176.719640] sd 6:0:0:0: Attached scsi generic sg2 type 0

[ 6176.725391] sd 6:0:0:0: [sdb] 6500800 512-byte logical blocks: (3.32 GB/3.09 GiB)

[ 6176.829643] sd 6:0:0:0: [sdb] Write Protect is off

[ 6176.829651] sd 6:0:0:0: [sdb] Mode Sense: 0f 00 00 00

[ 6176.829656] sd 6:0:0:0: [sdb] Assuming drive cache: write through

[ 6176.939642] sd 6:0:0:0: [sdb] Assuming drive cache: write through

[ 6176.940772]  sdb: unknown partition table

```

fdisk -l tells me its fat32:

```
Disk /dev/sdb: 3328 MB, 3328409600 bytes

4 heads, 16 sectors/track, 101575 cylinders, total 6500800 sectors

Units = sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System

/dev/sdb1              16     6500799     3250392    b  W95 FAT32

```

But I can't mount it, being as the partition table is unknown. 

```
dogbert graham # mount -t vfat /dev/sdb /mnt/usb

mount: wrong fs type, bad option, bad superblock on /dev/sdb,

       missing codepage or helper program, or other error
```

I've enabled anything FAT related in the kernel:

```
#

# DOS/FAT/NT Filesystems

#

CONFIG_FAT_FS=y

CONFIG_MSDOS_FS=y

CONFIG_VFAT_FS=y

CONFIG_FAT_DEFAULT_CODEPAGE=850

CONFIG_FAT_DEFAULT_IOCHARSET="iso8859-1"

CONFIG_NTFS_FS=y

CONFIG_NTFS_DEBUG=y

CONFIG_NTFS_RW=y
```

Is there anything else I might be missing in the kernel, or anywhere else I might have gone wrong? This is 2.6.39-r3, I'm using amd64.

Thanks

GrahamLast edited by marinheiro on Sun Jul 24, 2011 9:26 pm; edited 1 time in total

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## krinn

system message is telling you it's unknow partition table, not a know and valid partition table that then the system might try to use (and this time, it will imply the FS options from your kernel).

better check then your mac can read these partitions table

```
cat /usr/src/linux/.config | grep MSDOS

CONFIG_MSDOS_FS=m

CONFIG_MSDOS_PARTITION=y <----

```

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## marinheiro

You got it in one. Thank you so much.

Graham

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## mreff555

Hey, I'm having the same problem. However, all of the mentiond config flags are yes. 

I can create the partition with fdisk, however I cannot mount/read it, or make the partition with parted.

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## Roman_Gruber

You need proper kernel settings and maybe proper use flags with parted / gparted ...

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