This just started the other day. Macbook Pro says "Your disk is almost full" (I get the message every two minutes it seems). "About this Mac" said I had only a couple gigs left and so I deleted about 30 gigs worth of stuff and yet it still says I have no space left. After one delete of a 3-gig file, it actually said I now had even less space left. Something is wacky. It won't let me do some functions that would add files to the computer even though I know there is room. It's a MacBook Pro (Retina, 15-inch, Late 2013), running High Sierra.