Unable to Send message in micromax X505 ?

Hi, I have just buy an micromax X505 handset and i don't lyk this handset coz it giving me continuously problem from the when i own it. Now I stuck with it's message problem. I am sending a message b't when i click on send option it showing me continuously "No Enough Memory". Plz tell what kind of problems is this. I have already delete all the message in inbox and sent items menu. B't still stuck at this problem can anyone help me in dis ? Thanx in advance !

May be you need to restart phone becz I don't have any idea why this problem arises ?