mouse-test: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/mouse-test - from package: gpm

You may install the required package with command yum install {package}

Error in other languages:
mouse-test: bevel nie gevind nie
mouse-test: comandă negăsită
mouse-test: comando não encontrado
mouse-test: commande introuvable
mouse-test: command not found
mouse-test: käsku ei ole
mouse-test: không tìm thấy lệnh
mouse-test: komanda nerasta
mouse-test: Kommando nicht gefunden.
mouse-test: kommandot finns inte
mouse-test: komut yok
mouse-test: nie znaleziono polecenia
mouse-test: níor aimsíodh an t-ordú
mouse-test: no se encontró la orden
mouse-test: no s'ha trobat l'ordre
mouse-test: opdracht niet gevonden
mouse-test: parancs nem található
mouse-test: perintah tidak ditemukan
mouse-test: príkaz nenájdený
mouse-test: příkaz nenalezen
mouse-test: команда не найдена
mouse-test: командата не е открита
mouse-test: 命令找不到
mouse-test: コマンドが見つかりません