I copy my post from topic open in entry sector, may be this is a better place.
The untar way is a mess, it's impossible in my opinion obtain something.
The solution come downloading the core files with wget or whatever you want and install a HTTP server in your machine.
I start with SimpleHttpServer but the request maded by fahClient is unsupported, may be because in HTTP/1.0 I think for proxy compliance.
Tryng with NodeJs http-server I have success.
Simply reconstruct the path
/v7/lin/64bit/avx/
inside a directory, cd to it and here launch the server.
Insert in /etc/hosts file an entry like
127.0.0.1 cores.foldingathome.org
and now the client can download the files!
I hope this helps, but I think that the fahclient made the request in a measleading way
Workaroud for people stuck with "Update_Core" status
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