dropbox DOA

My dropbox desktop (MS365) seems to be dead in the water - no menu or status bar icon, and desktop app just quits after a few seconds when I start it.

Albeit powershell seems to recognize something or other running. Any help appreciated.

PS C:\Users\Jeremy Rutman> Get-Process dropbox

Handles NPM(K) PM(K) WS(K) CPU(s) Id SI ProcessName
------- ------ ----- ----- ------ -- -- -----------
360 25 47456 83732 5.33 7464 1 Dropbox
312 22 35336 60652 0.47 10716 1 Dropbox
14211 180 349716 429648 4,129.02 14880 1 Dropbox
187 12 2872 9144 0.00 15476 1 Dropbox
254 14 3408 13164 0.00 15580 1 Dropbox
473 24 20076 34400 0.02 15836 1 Dropbox
353 21 13972 26876 0.14 16304 1 Dropbox
312 21 24308 48572 0.08 16540 1 Dropbox