no, the Dropbox client version that still runs with Win XP is blocked from the Dropbox side. So it didn't help to try to prevent the client from updating.
The Dropbox client for XP no longer have access to the server and no longer can't connect into the server.
You still can upload files with CarotDAV on XP to your Dropbox account. But until now CarotDAV can't create a public link to the uploaded files.