ossim-band-merge: 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/ossim-band-merge - from package: ossim-core

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

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