Arch Linux pacman error: failed retrieving file

Although this has been answered, I encountered the same issue. I resolved it by updating my databases while installing. For instance:

sudo pacman -Syu elinks

I found an answer, thanks to jasonwryan's comment.

I tried lots of things to get my ethernet connection to work and it still didn't work till I researched the netctl command (https://wiki.archlinux.org/index.php/netctl, man netctl).

ls /etc/netctl revealed that there were no profiles in my /etc/netctl folder, so I ran

cp /etc/netctl/examples/ethernet-dhcp /etc/netctl
netctl start ethernet-dhcp

Before that, I had run (from https://bbs.archlinux.org/viewtopic.php?id=151483)

systemctl enable [email protected]
systemctl start [email protected]

And voila, the internet was working. Not sure which of the commands was responsible, but now it works.