wcd.exec: 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/wcd.exec - from package: wcd

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