avmcapictrl: 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:

/sbin/avmcapictrl - from package: isdn4k-utils

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

On Debian possible default full paths are:

/usr/sbin/avmcapictrl - from package: capiutils

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

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