wvSummary: 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/wvSummary - from package: wv

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

On Debian possible default full paths are:

/usr/bin/wvSummary - from package: wv

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

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