feed2imap-opmlimport: command not found

Have You tried accessing the binary with the full path?

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/feed2imap-opmlimport - from package: feed2imap

You may install the required package with command apt-get install {package}
Error in other languages:
feed2imap-opmlimport: bevel nie gevind nie
feed2imap-opmlimport: comandă negăsită
feed2imap-opmlimport: comando não encontrado
feed2imap-opmlimport: commande introuvable
feed2imap-opmlimport: command not found
feed2imap-opmlimport: käsku ei ole
feed2imap-opmlimport: không tìm thấy lệnh
feed2imap-opmlimport: komanda nerasta
feed2imap-opmlimport: Kommando nicht gefunden.
feed2imap-opmlimport: kommandot finns inte
feed2imap-opmlimport: komut yok
feed2imap-opmlimport: nie znaleziono polecenia
feed2imap-opmlimport: níor aimsíodh an t-ordú
feed2imap-opmlimport: no se encontró la orden
feed2imap-opmlimport: no s'ha trobat l'ordre
feed2imap-opmlimport: opdracht niet gevonden
feed2imap-opmlimport: parancs nem található
feed2imap-opmlimport: perintah tidak ditemukan
feed2imap-opmlimport: príkaz nenájdený
feed2imap-opmlimport: příkaz nenalezen
feed2imap-opmlimport: команда не найдена
feed2imap-opmlimport: командата не е открита
feed2imap-opmlimport: 命令找不到
feed2imap-opmlimport: コマンドが見つかりません