ne2k-pci-diag: 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/sbin/ne2k-pci-diag - from package: nictools-pci

You may install the required package with command apt-get install {package}
Error in other languages:
ne2k-pci-diag: bevel nie gevind nie
ne2k-pci-diag: comandă negăsită
ne2k-pci-diag: comando não encontrado
ne2k-pci-diag: commande introuvable
ne2k-pci-diag: command not found
ne2k-pci-diag: käsku ei ole
ne2k-pci-diag: không tìm thấy lệnh
ne2k-pci-diag: komanda nerasta
ne2k-pci-diag: Kommando nicht gefunden.
ne2k-pci-diag: kommandot finns inte
ne2k-pci-diag: komut yok
ne2k-pci-diag: nie znaleziono polecenia
ne2k-pci-diag: níor aimsíodh an t-ordú
ne2k-pci-diag: no se encontró la orden
ne2k-pci-diag: no s'ha trobat l'ordre
ne2k-pci-diag: opdracht niet gevonden
ne2k-pci-diag: parancs nem található
ne2k-pci-diag: perintah tidak ditemukan
ne2k-pci-diag: príkaz nenájdený
ne2k-pci-diag: příkaz nenalezen
ne2k-pci-diag: команда не найдена
ne2k-pci-diag: командата не е открита
ne2k-pci-diag: 命令找不到
ne2k-pci-diag: コマンドが見つかりません