picocom: 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/picocom - from package: picocom

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

On Debian possible default full paths are:

/usr/bin/picocom - from package: picocom

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

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