cscope-indexer: 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 CentOS possible default full paths are:

/usr/bin/cscope-indexer - from package: cscope

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

On Debian possible default full paths are:

/usr/bin/cscope-indexer - from package: cscope

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