pcb_backannotate: 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_backannotate - from package: geda-utils

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

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