WD Smartware Pro stopped backing up to Dropbox

Smartware suddenly stopped backing up to Dropbox. If I click the Dropbox backup destination, I get a message about an error 400 from an external server.
I can normally access the Dropbox via browser etc. and I have plenty of space.

Who knows what happened and what I can do about it?

Wijnand

Do you own one of the following devices, use link for list?

No, a MyCloud 4TB and a MyBook 6TB

Have you looked at this?

https://support.wdc.com/knowledgebase/answer.aspx?ID=9880

I missed that.
Thanks for the link…