tuxpaint-config: 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 Debian possible default full paths are:

/usr/bin/tuxpaint-config - from package: tuxpaint-config

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

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