This error occurs when your account is configured to disallow users from resetting their passwords. You can change it by following these instructions in the Help:
http://help.adobe.com/en_US/scene7/using/WSef8d5860223939e252d11c5b12edf45786c-8000.html
When this error occurs, clear both the browser cache and the Flash cache.
If the error still occurs, it is possible there are calls being blocked on the user's network.
For SPS to connect to the FTP server to get its folder structure, it submits URLs like so:
https://s7ftpX.scene7.com/webadmin?companyHandle=[handle]&path=&authorization=&action=getFileSystem&company=yourcompany&nocache=
(X changes based upon what region you are in; for example, 1 or 2 for US.)
Contact your IT and verify whether these requests get blocked.