xclips-color: 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/xclips-color - from package: clips-xclips

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

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