Missing Operating System


I had windows 7 for about half a year on this new pc, I had about half of HD unpartiotioned, was saving it to install MAC OSX later.

Today I activated that unused partitioned through windows disk manager, and Created another boot through EasyBCD befor installing OSX. Restarted PC, and now getting messege "Operating System not Found" when trying to boot.
tested HD, HD is ok not crashed.

Tried repairing through Win 7 DVD, no luck,
tried "system repair": OS doesn't apear ther
tried comand prompt: got messege "check if directory or something isn't corrupt" something like that.
ttried ultimate boot cd: could figure out how to do a repair

I don't care about OSX anymore, need Win7 to be running again (I have lots of audio samples and music projects,and music software, afraid I might loose them)


i just connected the hdd to another computer, and i could open and everything, so i guess the hdd isn't crashed.

I also deleted that raw unused hdd space that i was gonna partition with OSX.. and Still can't boot.

but now i get slighly different messege: "..not found..select a bootable device... restart.."

I tried repair form dvd again, OS doesn't show up there either
Last edited:
That's the problem with trying to install OS X on an unsupported environment - when things go wrong, they do so in most terrible ways!

Sounds like OS X fried your MBR. Try using a tool like TestDisk to search for and retrieve deleted partitions: TestDisk - CGSecurity
I never saw the "Addendum" to your post - must have left the tab open for a while then replied to it. Ignore what I said, if you can view the contents of the partition then you don't need testdisk. Listen to Terry, and use the recovery CD to put things right.
Good news!
I spent the whole night re-running Boot Repair automatic and ComandPromt, over and over again, than finaly by a miracle the Computer booted!! now when I boot i have a choice either Windows 7 or OSX(which isn't there).

When you say "activated", do you mean you flipped the "active" flag in Disk Management ?

I don't know, i haven't seen any flag, I went to Computer>manage>disk manger and right clicked on unused/unpartiotioned and selected "activate", than that Hd space was displayed as "RAW".

than i went to Easy BCD and added entry as OSX, but I still selected Windows 7 as default boot OS.

btw, I havent tried installing OSX before or after all this, I just tried to prepare the unpartioned hd sector to be ready to partiotned by OSX..
There's no "activate" in Disk Management right click dialogue. There is "Mark Partition as Active"
If you do that to an empty space, the PC cannot boot.
That flag ("active") tells the MBR where to find the boot files and programs, and should never be used for any space except a partition containing a bootable OS.
At some point during your long night, something you did set the W7 partition back as the active one (only one partition on a HDD can be active, so turning it on in one place, turns it off in its previous space) and the PC immediately became bootable again.
Have a read of the first link in the sticky thread. It's a very good tutorial on the boot process.