Maybe the creeperhost one doesn't have the firewall open to mojang and other connections like yours.I can login to any other server fine. I havent tried another modpack but creeperhost support is insisting that it's either mojang's fault or this pack's fault. I cannot find a thing on google that fixes this. My firewall has been disabled for months.
Here's what appears in my client log when I try to connect, any ideas?