我正在使用 ubuntu 12.04 LTS，网卡和互联网访问一切正常，但是当我使用 Ubuntu 软件中心安装 Samba 时失败；（我使用 Ubuntu 软件中心安装了其他软件，运行正常）
或者当我使用终端通过终端安装它时它说：
wiki@wiki-VirtualBox:~$ sudo apt-get install samba
[sudo] password for wiki:
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following extra packages will be installed:
libwbclient0 samba-common smbclient tdb-tools
Suggested packages:
openbsd-inetd inet-superserver smbldap-tools ldb-tools ctdb cifs-utils
The following NEW packages will be installed:
samba tdb-tools
The following packages will be upgraded:
libwbclient0 samba-common smbclient
3 upgraded, 2 newly installed, 0 to remove and 597 not upgraded.
Need to get 22.3 MB/22.4 MB of archives.
After this operation, 23.0 MB of additional disk space will be used.
Do you want to continue [Y/n]? y
Err http://us.archive.ubuntu.com/ubuntu/ precise-updates/main libwbclient0 i386 2:3.6.3-2ubuntu2.6
404 Not Found [IP: 91.189.91.13 80]
Err http://security.ubuntu.com/ubuntu/ precise-security/main libwbclient0 i386 2:3.6.3-2ubuntu2.6
404 Not Found [IP: 91.189.92.200 80]
Err http://security.ubuntu.com/ubuntu/ precise-security/main smbclient i386 2:3.6.3-2ubuntu2.6
404 Not Found [IP: 91.189.92.200 80]
Err http://security.ubuntu.com/ubuntu/ precise-security/main samba-common all 2:3.6.3-2ubuntu2.6
404 Not Found [IP: 91.189.92.200 80]
Err http://security.ubuntu.com/ubuntu/ precise-security/main samba i386 2:3.6.3-2ubuntu2.6
404 Not Found [IP: 91.189.92.200 80]
Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/s/samba/libwbclient0_3.6.3-2ubuntu2.6_i386.deb 404 Not Found [IP: 91.189.92.200 80]
Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/s/samba/smbclient_3.6.3-2ubuntu2.6_i386.deb 404 Not Found [IP: 91.189.92.200 80]
Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/s/samba/samba-common_3.6.3-2ubuntu2.6_all.deb 404 Not Found [IP: 91.189.92.200 80]
Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/s/samba/samba_3.6.3-2ubuntu2.6_i386.deb 404 Not Found [IP: 91.189.92.200 80]
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?
wiki@wiki-VirtualBox:~$
请帮忙