[ubuntu] Unable to mount when coecting any flash drive, exit status 16

Hello, i should say i'm using a live USB with persistence to try out ubuntu after my HDD fried.
The error above happens everytime i coect a flash drive, however, i can still access the flash drive.

Full error:

Unable to mount flash drive.

mount -t "..." exited with exit status 16: mount: can't open /etc/mtab for writing: input/output error.

When i do:

sudo gedit /etc/mtab

It fails to open with the same error, input/output.

How can i fix this?

Currently /media/ubuntu/ contains every mounted flash drive since i rebooted the computer and deleted the folders there, the problem is, i don't have any coected and if i coect another one, it adds one because i can't seem to unmount it, accessing each folder works even though there's no actual flash drive. It also repeats itself, like, drive1,drive2 (it's the same drive)

Can anyone help? I know i'm basically on live CD, but i was hoping this trip to linux would be easier than it's been... :/

Edit: I'm using ubuntu 14.04.4 LTS