I was about to try the latest OSMC on my Raspberry Pi3, and I needed to backup my microSD before proceeding.

I fired up my laptop, booted linux, and typed my usual dd (with a hint of of gzip because we don’t want 64GB of zeroes) and…

dd: opening `/dev/sdc': Read-only file system

The first thought was: “Fear not, padawan, it must be the SD lock”, so I checked and, to my dismay, nothing happens! I tried the usual reboot. Guess what? Nothing. Nada. Nichts.

Please, I just need to backup my microSD!

So I did what every developer do when things go awry: we go to stackoverflow. And of course SO was full of the usual:

  • try to fix permissions
  • reboot your machine
  • say a little prayer

Until i stumbled upon this answer, buried between others because of a low score:

You won’t believe this, but spraying compressed air into the card slot near where the read-only switch is sensed fixed it for me. I hardly believe it.

And to me it sounded like “if it’s stupid but it works, it’s not stupid”: I blew gently into the card slot, re-inserted the microsd, and BAM, it read & wrote as easy as 1-2-3.

Thank you, Ian