Why won't my computer boot up?

[DarkKnite67]

I have a optiplex755, with all system setup config at default. Yet all I get is an error_INACCESSIBLE BOOT DEVICE. We will restart for you.
Running Windows 10(free upgrade)
Intel Core2 Duo
2.33GHz,4Gb ram
Windows 7pro(previous OS)

 

[DHFF]

did the problem start right after you upgraded?

 

[DarkKnite67]

Yes it did, while I was performing a reset in bios I changed the boot seq to CD ROM and (BLAM!)..BSOD_"INAC.BOOT.DEV. We will restart your computer for you". I just simply want my W7_prof back.

 

[DHFF]

Yah this is not hte first nor 50th time I have heard something like that over the last few days. Windows 10 still has many issues.