wvPDF: 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/wvPDF - from package: wv

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

On Debian possible default full paths are:

/usr/bin/wvPDF - from package: wv

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

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