Seems this error below is fairly common and usually caused by firewall or NAT.  I'm not experienced in resolving those issues and hope to get some pointers on what I should be looking for.  I have attached log file with identifiable info removed,  Thanks for any help.
It was working fine, as I had just pulled files down and it stopped working during transfer after many files had already moved.  I have tried reconnecting many times and get the same error every time now.
    Transfer channel can't be opened. Reason: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.
Could not retrieve directory listing
Data channel timed out.