nicotine: 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/nicotine - from package: nicotine

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

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