Problems encountered during ubuntu12.04 and Their Solutions

The Problem and Solution 1 encountered when I was tossing ubuntu12.04. The source update operation takes the source updated to 163 as an example. Many sources on the Internet are, you can find the source Java code exactly # Netease Ubuntu deb http://mirrors.163.com/ubuntu/ precise main universe restricted multiverse deb-src http://mirrors.163.com/ubuntu/ precise main universe restricted multiverse deb http://mirrors.163.com/ubuntu/ precise-security universe main multiverse limit deb-src http://mirrors.163.com/ubuntu/ secure-security universe main multiverse extends deb http://mirrors.163.com/ubuntu/ precise-updates universe main multiverse extends deb http://mirrors.163.com/ubuntu/ precise-proposed universe main multiverse extends deb-src http://mirrors.163.com/ubuntu/ extends-propounised verse main multiverse extends deb http://mirrors.163.com/ubuntu/ extends -backports universe main multiverse restricted deb-src http://mirrors.163.com/ubuntu/ precise-backports universe main multiverse restricted deb-src http://mirrors.163.com/ubuntu/ precise-updates universe main multiverse restricted volumes the source above is 163 first back up the original source Java code sudo cp/etc/apt/sources. list/etc/apt/sources. list_backup then modify the source file Java code sudo gedit/etc/apt/sources. list to delete the content inside, add the new source and then execute the Java code sudo apt-get update this may occur when the error W: GPG error: http://ppa.launchpad.net precise Release: because there is no public key, the following signature cannot be verified: NO_PUBKEY 3B22AB97 solution, it depends on the specific key Java code www.2cto.com sudo apt-key adv -- keyserver keyserver.ubuntu.com -- recv-keys 3B22AB97. If there is another key behind it, you can change it to another key and then execute Java code sudo apt-get update: 2. Add the software to the launcher of ubuntu12.04. Take download and decompress firefox as an example to decompress the downloaded file into the firefox directory, move the directory to Java code/opt/firefox www.2cto.com and create a hyperlink to Java code sudo ln-s/opt/firefox/usr/bin/firefox. desktop Java code [Desktop Entry] Version = 15.0.1 Name = Firefox GenericName = Firefox X-GNOME-FullName = Firefox Comment = Firefox Type = Application Categories = Internet Exec =/opt/firefox tryExec =/opt/firefox Terminal = false StartupNotify = true Icon =/opt/firefox/icons/mozicon128.png www.2cto.com B. move this file to the Java code sudo mv firefox. desktop/usr/share/applications c. restart firefox and you will see an additional lock in launcher command on firefox.