Since I upgraded to Sierra, I am having FTP issues in that once connected to my remote server, it fails to retrieve the directory. I have been in touch with my host service and they have established that I do connect successfully to the server, so as far as they are concerned, that is not the issue. I am simply trying to FTP files from my Mac to a hosted server, not run my own FTP server. I manage several web sites for small voluntary groups, so my needs are fairly basic and I'm very familiar with this protocol. I learned a lot about Macs and PCs along the way in my previous jobs at a university, but was never a technician. I moved from Finance to providing desktop/networking support for both Macs and PCs back in the 90s until my retirement in 2002. I do not have the Firewall turned on. This is happening with every single account I try to FTP to and I am using Filezilla as my client. I have tried other FTP software with similar results. On El Capitan, the problem turned out to be the networking hardware MTU setting - once I changed that to be the same as the MTU setting on my router, it worked fine. I don't think that applies here as I am now using a cable/ethernet connection. On the cable gateway, the firewall is set as 'normal' and I do not control that setting, although I now have Port Blocking turned off in my internet service, at my request. Since I use a Mac, tech support eyes tend to glaze over a bit when it comes to offering solutions.... Admittedly, this sort of thing does not crop up when I use a Windows PC on the same network. I consolidated everything back to my Macs a couple of years ago and I really don't want to go there ever again.... Has anyone else come across this? Anyone found a solution? I went through all this stuff when I migrated to El Capitan and it took weeks for the eventual solution to show up, after much diligent searching - it was the MTU setting. Someone on another forum suggested I roll back to El Capitan - horrible thought! I don't think I have the patience nowadays to go though the hoops for that. Thanks everyone.