Fix exFAT External Hard Disk on Mac
Often times my External Hard disk stops being detected on my MacBook Air. The first few times were scary but now I generally know that I will figure a way out.
Why
It usually happens when the Hard Disk does not get ejected properly. I have read that exFAT on mac is vulnerable to such a scenario and the file system kind of breaks.
How to Fix It
There are two options. The first one is simple: Keep the hard disk connected and let Mac fix it by itself. I have noticed that if you give it approx 10-20 minutes, mac would by itself fix the File System. And optionally you can also try to run First-Aid
from Disk Utility
The other option is to use the following steps:
- Use
diskutil list
to find the right drive id. - You want the id under the IDENTIFIER column, it should look like
disk1s1
- Run
sudo fsck_exfat -d <id from above>
. egsudo fsck_exfat -d disk1s3
-d
is debug so you’ll see all your files output as they’re processed.- Answer
YES
if it gives you the promptMain boot region needs to be updated. Yes/No?
- Open Disk Utility and you should be able to repair here successfully.
Source of the above steps
Written on January 1, 2019