Right, so that's not the cause. (As an aside, the error messages you get from dropbox are not very helpful. In the first example, you get "KeyError: 'content-length'". In the last example, it suggests setting $http_proxy, while it is already set.)
Right, so that's not the cause.
(As an aside, the error messages you get from dropbox are not very helpful. In the first example, you get "KeyError: 'content-length'". In the last example, it suggests setting $http_proxy, while it is already set.)