My fujitsu fall down

Hello,

Hello,
i'm UWINDEMEYE,from in KIGALI INSTITUTE OF EDUCATION,my Fujitsu fallen down when i was trying to plug it .i immediately removed battery and put it again,i started it and showed me 'OPERATING SYSTEM DON'T FOUND'.I CLOSED AND CHECKED AGAIN AND FIND THAT THE HARD DISK WERE REMOVED(it was not fixed may ones repaired it and forget to fix the screw),i put the hard disk the fixed it with the screw,i restarted ,it showed me that it's going to start but in few minute it sopped and show me the message,saying that it didn't start due to the amovible software put,it asked me to restart but i find the same.

with grateful appreciation
Thank you