Chris Hamady

About a year ago, I bought a flush mount micro SD card adapter for my MacBook Air as well as a 128 gig micro SD card for it. I leave the SD card in the laptop 24/7 so that I can essentially have an additional 128 gigs of storage when I need it.

Soon after installing it, I noticed that occassionally (more like regularly), when attempting to copy data to the SD card, I would receive an error and the copy would fail. Nothing I tried would correct the issue and I ended up having to reformat the SD card in another computer numerous times. I looked all over the internet and could not locate a fix for this, which is why I'm writing it up.

I finally came up with a fix not requiring a reformat of the SD card. On your Mac, open Disk Utility. Select the SD card's mounted volume, NOT the root of the SD card partition. Once the mounted volume is selected, you can now click the "unmount" button and unmount the volume. Next, select the SD card's unmounted volume and "Repair Disk." Once completed, mount the volume again using the "mount" button in Disk Utility. The volume should once again be writable.

If the above doesn't work for you, try repairing both the volume and the root partition prior to mounting the volume again.

Chris