Hello, can you also send the logs of the server? You can find them in the game folder. The file is named server_logs.text.
Otherwise, Blue Stacks is known to create problems with the game. Another solution might be to authorize the server when Windows popups a window about python. You can also try to see if it comes from your anti-virus. AVG AntiVirus Free is known to create troubles during the installation, maybe this is something related.