slaptest: 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:

/usr/sbin/slaptest - from package: openldap-servers

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

On Debian possible default full paths are:

/usr/sbin/slaptest - from package: slapd

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

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