Ubuntu software center always gives proxy error

[caglar]

Binary package hint: software-center

Ubuntu software center always gives proxy error although i don't use any,i have never reboot it, i can use apt-get but not USC, and i tried on several mirrors.

Failed to fetch http://mirror.switch.ch/ftp/mirror/ubuntu/pool/main/e/emacsen-common/emacsen-common_1.4.19ubuntu1_all.deb 407 Proxy Authentication Required
Failed to fetch http://mirror.switch.ch/ftp/mirror/ubuntu/pool/main/e/emacs23/emacs23-common_23.1+1-4ubuntu7.1+maverick1_all.deb 407 Proxy Authentication Required
Failed to fetch http://mirror.switch.ch/ftp/mirror/ubuntu/pool/main/e/emacs23/emacs23-bin-common_23.1+1-4ubuntu7.1+maverick1_i386.deb 407 Proxy Authentication Required
Failed to fetch http://mirror.switch.ch/ftp/mirror/ubuntu/pool/main/a/anthy/libanthy0_9100h-6ubuntu1_i386.deb 407 Proxy Authentication Required
Failed to fetch http://mirror.switch.ch/ftp/mirror/ubuntu/pool/main/libo/libotf/libotf0_0.9.10-1_i386.deb 407 Proxy Authentication Required
Failed to fetch http://mirror.switch.ch/ftp/mirror/ubuntu/pool/main/m/m17n-lib/libm17n-0_1.5.5-1_i386.deb 407 Proxy Authentication Required
Failed to fetch http://mirror.switch.ch/ftp/mirror/ubuntu/pool/main/e/emacs23/emacs23_23.1+1-4ubuntu7.1+maverick1_i386.deb 407 Proxy Authentication Required
Failed to fetch http://mirror.switch.ch/ftp/mirror/ubuntu/pool/main/m/m17n-db/m17n-db_1.5.5-1_all.deb 407 Proxy Authentication Required
Failed to fetch http://mirror.switch.ch/ftp/mirror/ubuntu/pool/main/m/m17n-contrib/m17n-contrib_1.1.10-1_all.deb 407 Proxy Authentication Required

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: software-center 3.0.7
ProcVersionSignature: Ubuntu 2.6.35-25.44-generic 2.6.35.10
Uname: Linux 2.6.35-25-generic i686
NonfreeKernelModules: nvidia
Architecture: i386
Date: Tue Mar 1 14:23:24 2011
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release i386 (20101007)
PackageArchitecture: all
ProcEnviron:
 LANG=en_US.utf8
 SHELL=/bin/bash
SourcePackage: software-center