Problems with wireless network

I have been using WinScp for years. Recently I switched to a wireless network. Since then I cannot attach. I got an incomprehensible error prior. Having loaded 3.7.4 Build 271 I now get the message "Network error : Network is Down". It isn't otherwise I wouldn't be sending this

When I "hardwire" into the wireless hub it works fine!

Any hints?

Are you able to connect using Putty SSH client?