我跑
sudo apt-get update
最后返回这些失败：
W: Failed to fetch httpe://archive.ubuntu.com/ubuntu/dists/raring/main/binary-amd64/Packages Protocol httpe not supported or disabled in libcurl
W: Failed to fetch httpe://archive.ubuntu.com/ubuntu/dists/raring/multiverse/binary-i386/Packages Protocol httpe not supported or disabled in libcurl
E: Some index files failed to download. They have been ignored, or old ones used instead.
我该如何解决这个问题？我环顾四周，似乎找不到答案。
运行后
lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 14.04.3 LTS
Release: 14.04
Codename: trusty
apt ×1