pycard-import: 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/pycard-import - from package: pycarddav

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