If you're in charge of a company or running a professional administration service, you'll need some a solid FTP server.
G6 FTP Server is about as advanced as FTP servers get - highly advanced and packed with features. It works via any Windows defined account and features advanced encryption at every stage. You can choose who can and cannot connect to your sever plus define a maximum and minimum level of connections. You can create unlimited accounts but the good thing is that you can set a date for expiration so they won't last forever. It's also very flexible in that any changes you make do not require you to restart the whole server - they take place in realtime. In addition to all this, there's also an events logger - useful for logging unauthorized logins or attacks - plus you can schedule and limit bandwidth usage according to what you are doing on the server at any one time. There are also options to resume and pause downloads as well as check the validity and integrity of connections currently established.
An extremely powerful FTP server that's not for the faint-hearted but will provide for just about any company's needs.