pscp.pssh: 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/pscp.pssh - from package: pssh

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

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