defncopy: 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/defncopy - from package: freetds

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

On Debian possible default full paths are:

/usr/bin/defncopy - from package: freetds-bin

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

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