mecab: 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 Debian possible default full paths are:

/usr/bin/mecab - from package: mecab

You may install the required package with command apt-get install {package}

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