Thanks for your feedback.
I wanted to open a new connection recently, and I got the error "Network error: Permission denied". I suspected it being some auth issue, and after some longer search did I realise that due to some external settings WinSCP was blocked from network access.
I think the plain message – "Network error: Permission denied" is confusing and not really obvious – it's not clear that the permission error is FOR the network, not from a remote host. I tried to look the generated logs but there is also just this message and no context given.
I think a similar message would be more clear: "Network access denied". Some other text would also be helpful, like "Check if some permissions or a firewall blocks WinSCP from accessing the network".