pvrenderserver: 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/pvrenderserver - from package: paraview

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

On Debian possible default full paths are:

/usr/bin/pvrenderserver - from package: paraview

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

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