Due to the extremely high popularity of our virtual FTP server hosting service, our FTP system experienced slow performance in the last 2 weeks. We have just added our FTP server capacity. If you are connecting today, it should be working fine.

We closely monitor our system. At this time, we have a huge number of concurrent FTP connections and we don't have any reported problems.

Your error message seems to be caused by some firewall software / security software blocked FTP. In this case, you can also try DriveHQ FileManager, which uses HTTP/HTTPS.