No more signal for my external monitor

Hello everybody.

I used to connect my macbook to an external monitor using a DVI adapter. Up to yesterday all worked fine.

Yesterday I unplugged my macbook from my monitor and I take it away.
I came back at home and suddendly there is no more signal on this external monitor!
Do you know how this is possible? Any idea to understand at least where is born the issue?

Thanks!

Bye