Hey guys, sorry for not posting much the last few months. Trying to do that more often from now on, I'll have to use my tablet for it the mean time because my computer is not working probably. I hope someone can help me with my problem

I am getting this message over and over again
When I turn on the computer it loads every thing up, 5 minutes later, it's shows a blue screen with (from what I can remember) the following
It has a problem and has to reboot itself, data has to be collected, after that the computer will reboot itself up, it sure is taking his time to do that sometimes, sometimes ithe takes 5 or 10 minutes but sometimes he is doing that for almost half a day?!
After he is done doing that, he reboots itself up and shows me this message

Reboot and select proper boot device
Or insert boot media in selected boot device and press a key



some people I know looked into the problem, and the pc shows us another message that the hard drive is not working properly so one of the 2 hard drives could be broken... we also used a program to show if the harddrives working properly but program says their both working fine,
They tried some other things out but it didn't work in the end

it seems that one of them is not working
That's kinda it, I hope you guys can help me with this :(
If you have any questions, feel free to ask

(Sorry for my writing, I was tired while writing this)