merge-info: 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/merge-info - from package: xstow

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

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