Comment # 4 on bug 907403 from Mark Fairbairn

sorry about the late reply.
Dropbox accounts created prior to 2013 by default were created with a "Public"
folder so for accounts created before this time servicemenu works fine.
However, from around 2013 onwards Dropbox changed the way files were shared
publicly so the need for a public folder was removed so not created in accounts
by default.

It is possible to add a "Public Folder" but only in premium dropbox accounts -
so if working with a free dropbox account created after 2013 then the
servicemenu produces the errors stated in the initial bug report.