I'm the arch Mage at the mages guild I just want to know how to reach master wizard rank.

Uh, Master-Wizard is the rank below Arch-Mage. You had to have achieved it before you could become Arch-Mage.

Ok I guess mine glitched because I don't have the master wizard achievement but I have the arch Mage achievement.

Raminus Polus is a Master Wizard. As Arch Mage you are his boss.

The reason for missing that rank is because the game forces you to ask for a promotion after the Vatchen (sp?) quest. In most cases promotion is forced on you, but you can miss that promotion if you don't explicitly ask for it. If you don't ask for it back at Vatchen you skip the Master Wizard rank.