Q: MacBook Pro says hard drive is almost full, start up disk is full. What do I do to make space?

Hi Taylorlaura, if you can use your Mac then move your own large data files over to another disk, until you make about 50 GB of space.

OS X: What is "other" space in About This Mac? - Apple Support

Then download and run Omni DiskSweeper. It can show you the precise size and location of all your files. It will inventory your disk starting from the files that take up the most space. It can also give you a more accurate read of disk space than Finder or Storage Tab of About this Mac. If you want you can even delete files from OmniDisk Sweeper. But be careful some of the items may be important to your system.

You can quickly get a little bit of working space by deleting everything in your "Downloads" folder. Anything thrown out in error can be downloaded again later.

This will not solve the problem, but it may keep your Mac from crashing immediately while you follow up with macjack's advice. OmniDisk Sweeper is about 5MB in size.

I use Grandperspective http://grandperspectiv.sourceforge.net/ and enjoy it.

taylorlaura wrote:

 

Ok, thank you. You say to move some files (music, docs, etc) to my external hard drive? And then get the Onmi Sweep.

Yes.

Disk Space - Free Up

Disk Space – Free Up (2)

Disk Space - Free Up - Mavericks