Last year, Dropbox announced that they were going to turn off the first version of their API (v1). The turn-off date was eventually set for 28th September 2017 (today).
Accordingly, we developed support for v2 of the Dropbox API (which remains the latest/current version), and released it in UpdraftPlus 1.12.26 (free) / 2.12.26 (paid) in mid-November 2016.
The set day has arrived, and Dropbox have turned off their old API. So, if you’ve not updated UpdraftPlus for over 10 months, and are using Dropbox, then as of today: 1) it won’t work, and 2) the solution is simple: upgrade to a current UpdraftPlus release. (If you need to renew your UpdraftPlus Premium licences, then you can do so via a fresh purchase from our shop).
David Anderson (lead developer).