openchangeclient: 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/bin/openchangeclient - from package: openchange-client

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

On Debian possible default full paths are:

/usr/bin/openchangeclient - from package: openchangeclient

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

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