Thanks for contacting us with your error log, sorry you've again encountered a problem with this.

I see in NCBI's web logs that your first step (whose logging output you've given above)
succeeded in reaching our web host.

So the network access verification we have in place as part of RAPT is the next place to check and for us to fix.

We tested on linux hosts running docker; it looks like there are some differences in how networking is handled by MacOS running docker. To help us understand what's happening, could you share the version of Docker and the OS version that you are running?

Thank you for your reply. I'm running Docker 18.09.6 under Ubuntu 16.04. Anyway, you say I'm successufully reaching your web host but the error log's stated the message "problem with tcp access to ncbi.gov sdl host".

Originally posted by @mglgc in #8 (comment)