icewmtray-lite: 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/icewmtray-lite - from package: icewm-lite

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

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