pcb-gtk: 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/pcb-gtk - from package: pcb-gtk

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

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