see that you have a good connection with internet, best is a cable.
Just wait if an error occurs, x5 will automaticly retry a little later.

Hello. Try one of these:

1. Temporarily disable the antivirus and firewall.
2. Do not use VPN or proxy.
3. Try not to use other programs that greatly affect Internet connection during upload.
4. Try connecting directly to the Internet rather than through intermediate network devices.