Dreamweaver 2017.5 won't connect via FTP to 1&1 server

I have been using 1&1 for my Web site server for many years. I have used Dreamweaver for building my Web sites for many years. I have never had any problem with Dreamweaver making an FTP connection to 1&1 for uploading my files. However, with the latest Dreamweaver (2017.5) I cannot get it to connect with any settings. I have tried FTP, SFTP, Passive on and off, Performance optimizations on and off. I've turned off Anti-virus and Firewall. Nothing works. However, when I attempted a connection using Beyond Compare's FTP feature, the connection was immediately made and I was able to upload my files with no problem.

Can anyone help me get this working? I prefer to upload through Dreamweaver rather than a separate program.

Here's the error message I get every time I try to connect.