tab2graph: command not found

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/tab2graph - from package: perl-Text-RecordParser

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

On Debian possible default full paths are:

/usr/bin/tab2graph - from package: libtext-recordparser-perl

You may install the required package with command apt-get install {package}

Error in other languages:
tab2graph: bevel nie gevind nie
tab2graph: comandă negăsită
tab2graph: comando não encontrado
tab2graph: commande introuvable
tab2graph: command not found
tab2graph: käsku ei ole
tab2graph: không tìm thấy lệnh
tab2graph: komanda nerasta
tab2graph: Kommando nicht gefunden.
tab2graph: kommandot finns inte
tab2graph: komut yok
tab2graph: nie znaleziono polecenia
tab2graph: níor aimsíodh an t-ordú
tab2graph: no se encontró la orden
tab2graph: no s'ha trobat l'ordre
tab2graph: opdracht niet gevonden
tab2graph: parancs nem található
tab2graph: perintah tidak ditemukan
tab2graph: príkaz nenájdený
tab2graph: příkaz nenalezen
tab2graph: команда не найдена
tab2graph: командата не е открита
tab2graph: 命令找不到
tab2graph: コマンドが見つかりません