# vi /etc/apt/sources.list
去掉光盘源，并增加non-free contrib，最后可能是这样的：
deb http://debian.cn99.com/debian/ stable main non-free contrib
deb-src http://debian.cn99.com/debian/ stable main non-free contrib
#deb http://ftp.hk.debian.org/debian stable main non-free contrib
#deb-src http://ftp.hk.debian.org/debian stable main non-free contrib
deb http://security.debian.org/ stable/updates main non-free contrib
deb-src http://security.debian.org/ stable/updates main non-free contrib
然后运行
# aptitude update
# aptitude upgrade
