dbcheck: 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/lib/debug/usr/sbin/dbcheck - from package: bacula-director-mysql-dbg
/usr/lib/debug/usr/sbin/dbcheck - from package: bacula-director-pgsql-dbg
/usr/lib/debug/usr/sbin/dbcheck - from package: bacula-director-sqlite3-dbg
/usr/sbin/dbcheck - from package: bacula-director-mysql
/usr/sbin/dbcheck - from package: bacula-director-pgsql
/usr/sbin/dbcheck - from package: bacula-director-sqlite3

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