tkabber: 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/tkabber - from package: tkabber

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

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