tek2plot: 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/tek2plot - from package: plotutils

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

On Debian possible default full paths are:

/usr/bin/tek2plot - from package: plotutils

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

Error in other languages:
tek2plot: bevel nie gevind nie
tek2plot: comandă negăsită
tek2plot: comando não encontrado
tek2plot: commande introuvable
tek2plot: command not found
tek2plot: käsku ei ole
tek2plot: không tìm thấy lệnh
tek2plot: komanda nerasta
tek2plot: Kommando nicht gefunden.
tek2plot: kommandot finns inte
tek2plot: komut yok
tek2plot: nie znaleziono polecenia
tek2plot: níor aimsíodh an t-ordú
tek2plot: no se encontró la orden
tek2plot: no s'ha trobat l'ordre
tek2plot: opdracht niet gevonden
tek2plot: parancs nem található
tek2plot: perintah tidak ditemukan
tek2plot: príkaz nenájdený
tek2plot: příkaz nenalezen
tek2plot: команда не найдена
tek2plot: командата не е открита
tek2plot: 命令找不到
tek2plot: コマンドが見つかりません