xpaint: command not found

Have You tried accessing the binary with the full path?

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/xpaint - from package: xpaint

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

On Debian possible default full paths are:

/usr/bin/xpaint - from package: xpaint

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