setstyle: 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/setstyle - from package: WindowMaker

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

On Debian possible default full paths are:

/usr/bin/setstyle - from package: wmaker

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

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