mod2osis: 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/mod2osis - from package: sword

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

On Debian possible default full paths are:

/usr/bin/mod2osis - from package: libsword-utils

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

Error in other languages:
mod2osis: bevel nie gevind nie
mod2osis: comandă negăsită
mod2osis: comando não encontrado
mod2osis: commande introuvable
mod2osis: command not found
mod2osis: käsku ei ole
mod2osis: không tìm thấy lệnh
mod2osis: komanda nerasta
mod2osis: Kommando nicht gefunden.
mod2osis: kommandot finns inte
mod2osis: komut yok
mod2osis: nie znaleziono polecenia
mod2osis: níor aimsíodh an t-ordú
mod2osis: no se encontró la orden
mod2osis: no s'ha trobat l'ordre
mod2osis: opdracht niet gevonden
mod2osis: parancs nem található
mod2osis: perintah tidak ditemukan
mod2osis: príkaz nenájdený
mod2osis: příkaz nenalezen
mod2osis: команда не найдена
mod2osis: командата не е открита
mod2osis: 命令找不到
mod2osis: コマンドが見つかりません