Try reindexing spotlight:
- Go to System Preferences>Spotlight
- Go to the Privacy tab, and add Macintosh HD the list.
- Restart/Reboot your Mac.
- Go back to System Preferences>Spotlight>Privacy and remove Macintosh HD from the list.
WARNING: This will consume large amounts of power (at first you can expect about 1% of power loss every 15 seconds or so, but it will slow considerably). It will also slow you computer considerably, using up almost all of one of your CPU cores, and about 2 GB ram. This is from my experience on a 1 TB hard drive, so it may be less or more intense for you.
P.S. Plug in your charger before doing this.
Figured out the issue for my case.
If the folder is not there, you can ignore the rest of this post.
ls. If there's anything in here then it's probably the cause or a significant contributor to your issue..
sudo chmod -R 777 ./Enter your password and type
rm -rf ./
And yeah this is relatively safe to do. The files are just core dumps (basically diagnostic logs that are generated when your computer crashes, as far as I know)
The storage tab in my Top Left Corner->About This Mac instantly registered the 150GB that was just made available.