letuknowit@ubuntu:~$sudo apt-get install mysql-client [sudo] password for letuknowit: Reading package lists… Done Building Dependency Tree Reading State Information… Done E: Unable to locate package mysql-server E: Unable to locate package mysql-client letuknowit@ubuntu:~$

I found the problem was that I changed the source of the software before executing sudo apt-get install, but I forgot to update it, so I executed the following command:

sudo apt-get update

Sudo apt-get install sudo apt-get install sudo apt-get install Unable to locate packet Unable to locate packet

Attached is another article:
The original address: http://blog.chinaunix.net/uid-22002627-id-3475650.html
Encounter this problem after find this thread is turned around When use apt – get update package often appear error Unable to locate the package update, especially in the ubuntu server, the solution is: to update the apt – get # sudo apt – get the update after the execution, problem solved. #sudo apt-get install mysql-client
#sudo apt-get install mysql-client
#sudo apt-get install mysql-client