eplain: 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/eplain - from package: texlive

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

On Debian possible default full paths are:

/usr/bin/eplain - from package: texlive-formats-extra

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

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