nepomukservicestub: 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

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/nepomukservicestub - from package: kdebase-runtime

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

On Debian possible default full paths are:

/usr/bin/nepomukservicestub - from package: nepomuk-core-runtime

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