USB flash drive mysteriously becomes read-only.

[GottaBuild]

Hello. I am using Knoppix on a PC with no hard drive, just a 1GB SanDisk USB flash drive which mounts automatically as sda1. This flash drive does NOT have a read-only mode switch. Everything was working fine for a few days, but now I can't write to the flash drive any more. For example, if in BASH I enter...

cd /mnt/sda1
mkdir MyNewFolder

...then I get the message "cannot create directory 'MyNewFolder': - Read-only file system". Similar messages appear when attempting to save documents, etc.

When I examine privileges with the command...

ls -ld

...then I get "drwxrwxrwx 5 knoppix knoppix 16384 Dec 31 1969"

Based on my very limited knowledge this looks like the flash drive should be writeable. Any pointer for the Linux newbie on how to fix this will be greatly appreciated.

[ruymbeke]

Hello. I am using Knoppix on a PC with no hard drive, just a 1GB SanDisk USB flash drive which mounts automatically as sda1. This flash drive does NOT have a read-only mode switch. Everything was working fine for a few days, but now I can't write to the flash drive any more. For example, if in BASH I enter...

cd /mnt/sda1
mkdir MyNewFolder

...then I get the message "cannot create directory 'MyNewFolder': - Read-only file system". Similar messages appear when attempting to save documents, etc.

When I examine privileges with the command...

ls -ld

...then I get "drwxrwxrwx 5 knoppix knoppix 16384 Dec 31 1969"

Based on my very limited knowledge this looks like the flash drive should be writeable. Any pointer for the Linux newbie on how to fix this will be greatly appreciated.

Did you try to right-click in the /dev/sda1 desktop icon and enable the wite access ?
If you type "mount" from a bash shell, do you have the "rw" flag or only "r" flag ?
Are you sure that the root directory (/) is mounted as /dev/sda1 ?
(use the "df" command from bash to check)
Hope this helps,
Gilles