ps2pk: 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/ps2pk - from package: texlive

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

On Debian possible default full paths are:

/usr/bin/ps2pk - from package: texlive-binaries

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

Error in other languages:
ps2pk: bevel nie gevind nie
ps2pk: comandă negăsită
ps2pk: comando não encontrado
ps2pk: commande introuvable
ps2pk: command not found
ps2pk: käsku ei ole
ps2pk: không tìm thấy lệnh
ps2pk: komanda nerasta
ps2pk: Kommando nicht gefunden.
ps2pk: kommandot finns inte
ps2pk: komut yok
ps2pk: nie znaleziono polecenia
ps2pk: níor aimsíodh an t-ordú
ps2pk: no se encontró la orden
ps2pk: no s'ha trobat l'ordre
ps2pk: opdracht niet gevonden
ps2pk: parancs nem található
ps2pk: perintah tidak ditemukan
ps2pk: príkaz nenájdený
ps2pk: příkaz nenalezen
ps2pk: команда не найдена
ps2pk: командата не е открита
ps2pk: 命令找不到
ps2pk: コマンドが見つかりません