Close button wont work

After opening any other window (other than our home window), when i press close button, it takes me to the buying page. The close button appears dimmed . I have to reload the whole game once more from begining to fix, otherwise the whole game is hanged. There is often a situation like this. Is this fault of my computer or any other fault? Plz help.
wait 5 seconds ...its probably a trick to make you think longer about buying something