Hi guys. OS is not booting up

I have been using Win 7 home premium for a long time now, but two days ago when I was starting the machine, a black screen came up saying that Boot file or something wasn't found, so I couldn't use the system.

I installed a fresh system already, but, how can I make windows to repair the damaged file? I have an original Windows 7 dvd. I tried, but it didn't give me any options related to repair.

Thanks in advance everyone. It is just for prevention in a future.

What is the exact error message? Bootmgr is missing?

Have you set the Win7 HD as first HD to boot first in BIOS setup? Check now.

When reinstalling follow these steps to get a perfect Clean Reinstall - Factory OEM Windows 7 .

Hey buddy, thanks for the promt reply. Regarding the message. Well, unfortunately I don't remember, but I'm sure it was a very short one. For example, once, my big PC used to show me a message saying

"FATAL ERROR: Failed to locate neccessary tablet (s) to make adjustments. Press any key for booting.

Ok, it isn't the same case, but I put an example of this, because I took a picture
And my solution was to reinstall the OS. Also, this same system had a problem that everytime I played a game it stoped working and the audio keep playing, but no video at all. I don't if it was the system, or the video card. I reinstalled the system, but never found out what was the problem, because I bought a new card.

Now, regarding the main topic here. As I said, I failed to gat the details. I was looking online to see if I could provide you a visual idea of what I'm talking about, but I didn't find a thing.
I can describe what happened. A day before It was working fine, but I have being having problems with a HD. I got two HD, both Western Digital which I believe are the best in reliability. But I couldn't tell what I downloaded, or what I could have done, but my second hard drive did appeared on my BIOS, but not in the system. I went to Computer, Manage, and the HD was there, but as Unallocated device. I tried to inialize it but I got an error saying that "the was a problem with the I/O" something like that.
After I did the reinstallation, I got it back operational, but after I finished installing the drivers yesterday, it went off again. I don't know man. What do you think it might be? I remember installing drivers that had to do wih the hard drive, but I simply don't know what is going on. I downloaded the drivers from dell.com (I got an Alienware 17r2) and no warranty haha nice ha?

Appreciate your help and time buddy. Thanks in advance to anyone who could give me some advises.

I suggest you read the steps in the Clean Reinstall tutorial so you now what methods work best. I would also always unplug all other HD's and peripherals during reinstall.

I asked you if your Win7 HD is set first to boot in BIOS setup. You never replied to that.

I'm sorry buddy, I missed that one. I will have to get into the BIOS to see what it says. What is your recommendation on it?
I gonna read that article about the clean install. It sounds good, and will be a great if I could follow those instructions for a better system.

Thanks for your time Gregrocker.

The Win7 HD needs to remain set as first HD to boot or it will error with Bootmanager is missing. I thought that might be the error to which you were referring as it is common and you confirmed you were messing with two HD's.

Let us know if you have any questions or need any further help. Remember to unplug all but the Win7 target HD and plug it into first SATA port before reinstall.

Thank you very much. I have planned to do it tomorrow, so I will let you know how it went

This information you are giving us, is just amazing. I really appreciate your help.

Once again, thanks.

Hi greg. Well here I send you an image, so you know what is happening. I was installing some windows updates, and the machine asked me for restart. Ok, I did it and here I am. The same problem. Thanks god I followed your instructions and made a recovery image. I'm working on it right now, but it is really pissing me off man. What is going on here?

Here is the image

Make sure Win7 HD is still the HD set first to boot.

Since you suspect this resulted from Updates first try booting into System Recovery Options to System Restore before the updates were installed.

Then work through these steps for Troubleshooting Windows 7 Failure to Boot.

If nothing helps then try wiping the HD with Diskpart Clean Command before Clean Reinstalling, accessing DISKPART At PC Startup