This is a very strange problem. We were not able to duplicate the problem on any of our test computers. The problem seems to be caused by some anti-virus software, or proxy server.
Anyway, we are working on a fix; if it goes well, it will be working fine in 1-2 days.
In the meantime, please check your browser settings, check if you are using any proxy server, anti-virus software, etc. You can also try DriveHQ FileManager 4.0 client, or use FTP to access DriveHQ Online Storage. You can even use Windows Explorer directly, just enter: