sync_smtpsearch: 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/sync_smtpsearch - from package: libruli-bin

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

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