My folders seem to be stuck syncing, but the Dropbox app is up to date (v225.4.4896).

This is becoming frustrating because I have replied to the forum message but my reply + screen shots seem to have disappeared. I will try again, without any screen shots.

I logged out of Dropbox and logged back in again and I received a start-up message that there was insufficient disk space. I requested 'Synch Everything' and it indexed and synched for several hours. No improvement ~  lots of folders unsynched (back to back double arrows icon).

So, I backed up data to a spare drive and deleted about 40Gb of data off the hard drive and tried again. i.e. log out of Dropbox, reboot PC, restart Dropbox. Similar result with a start-up message that insufficient space on hard disk. "Your Dropbox account (152.5GB) is too large to fit on this computer (72.0 GB remaining). However, much of my Dropbox is already synched so 72 GB ought to be enough to synch the remainder of the folders.

Everything thing was OK before the Dropbox app update on Wed 28th May. On my 465GB SSD disk, my 192GB of Dropbox folders/files was fully synched between my hard-disk and Dropbox cloud. I had in excess if 30GB spare disk space. 

I seem to be in a situation where I have to delete my Dropbox data (!) so that I have enough disk space to synch it!