We’re leaving for holiday tomorrow, so *of course* I decided that it was the *ideal* time to fix the album art in our music connection.  Don’t ask.

I found that I couldn’t access the windows (samba) share on my Raspberry Pi without it being read only.  Two hours of testing later I worked out that it was switching to read only when I tried to edit a file on it from the Windows machine.  Much googling later I worked out that it was probably a self defence mechanism of the disk switching to read-only because it had problems.

I knew it had problems but had ignored them.

A little googling later and I had downloaded dosfstools, unmounted the disk and run

sudo dosfsck -r /dev/sdsa1

repeatedly until it had no errors.  Then it worked perfectly.