Recently I bought a new HD due to "Operating System not Found" message and because my old HD was broken (at least I thought so).

When I plopped my new HD into my laptop, i reinstalled Windows Vista x64 home using the OS Disc. And then it was all working well, when the computer froze while on the desktop....I hard shutted down when, all of a sudden, I get a \boot\BCD 0x000000f error.

So...through CMD on the OS Disk, I deleted/made a new boot record on the C:

I restarted the computer....
And then I get this message:
"Windows failed to start. A recent hardware or software change might be the cause.
To fix the problem:
1. Insert your Windows installation disc and restart the computer.
2. Choose your language settings and click next.
3. Click "repair your computer"
----
4. Safe Mode
5. Safe Mode with networking
6. Safe Mode with Command Prompt
7. Last known good configuration
8. Start Windows normally"



***I tried using the repair computer option through the OS disc but to no avail. Whenever I restart the computer (it actually restarts automatically), I get the same message. The message goes back and forth with an error that I had gotten before I bought this new HD:

"For Realtek RTL8101E 10/100 PCI-Express Ethernet Adapter v1.03 (070618)
PXE-E61: Media test failure, check cable
PXE-M0F: Exiting PXE ROM
Operating System not found"

**I took out the brand new HD drive that I put into the laptop and put it in an external enclosure, and it is now connected to the laptop... I keep getting those two messages!!! plzzz help.....

EDIT: When I start Windows normally from the options....It seems like it is working when it suddenly restarts for some reason.

Can you check the cable(s) to see if somethngs wrong there? It looks like somethings going on with your PCI slots. How old is the laptop? You might have to have a repair technician look at it