Black screen says, "Unbootable device... press any key to continue"

[Aja Hara]

Hi I'm new here and with the mac.

So, last time i tried to install windows Xp in my mac book. It succeed.

I removed the windows Xp partition yesterday through the bootcamp in the mac partition.
Later, when i restart the mac book.. "the black screen" appears after the white screen with the "welcome" sound.. and it says Unbootable something and it stops there.

The funny thing is, I still can access the mac but i need to press alt/opt key after the white welcome screen.

Can you guys help me to make the black screen go and when i restart the mac, i can go directly to mac?

[Aja Hara]

bump bump