Accidentally marked drive C as active

I started O&O partition manager and accidentally pressed active on partition C and now I cannot boot windows...

I am using build 7600 x86 I loaded up the windows 7 iso on a usb memory and booted from it and chose repair, it said it found things to repair, i pressed ok, it rebooted but it did not help, now I chose from the repair menu to automatically search and fix, it said startup repair cannot repair this computer automatically and it want to send information about this problem, I wonder how it figured on doing that...

oh yes i started the repair again and pressed command promt and followed this guide: http://www.sevenforums.com/tutorials/20864-mbr-restore-windows-7-master-boot-record.html and the first thing it said about D being the "DVD" was wrong in my case, it was E and from then on the guide was excally like in my case and I completed the guide, rebooted and still the same message "BOOTMGR is missing Press ctrl alt del to restart"

So what can i do to fix this? without needing to reinstall windows

If you can reach the Recovery environment thru usb, open command prompt and type:
C: (Press Enter)
diskmgmt.msc (Press Enter)
See if you can open disk management, if yes, revert the changes that you made.

i got to the stage where i entered diskmgmt.msc and it said that it was not recognized as an internal or external command bla bla...

when you open command prompt, by default, it will stay on X:
You'll need to come to C drive and then type diskmgmt.msc

i typed dir and it seems to be my C: drive, does how do i enter the 100mb partition? where i can type diskmgmt.msc?

Or, on the C:\ prompt,
type the following commands and press enter.
diskpart
list volume
select partition C
inactive

Reboot your computer.

i typed in diskpart and this is what it says:

actually I´m gonna include a picture, that should explain more clearly.

now type select partition X (where x is the partition you marked active)
then type inactive
Restart your pc.

yeah i did that, then rebooted and it booted direcly from the usb memory, i disconnected it and now there wasn´t even a bootmgr error anymore, thanks anyway, I screwed the pooch on this one, Reinstall...

sad to hear that.

You had to make System Reserve active. Couldn't just remove active from one partition then nothing would be active. (Only one partition can be active at a time.)

please do like done in the below picture. you have to select the system partition.

Dinesh I can't tell you how long and hard I've struggled with this problem. You are the ONLY correct answer I could find. I created this account just so I could contact you and tell you how amazing you are. I'm glad you're in India, because if you were in the States, I would find you, and I would kiss you.

Welcome to our forum RossESmithIII.

We haven't heard from Dinesh for a while so I will give you a big thank you on his behalf.

Dinesh Last Activity: 20 Oct 2016

Just hang around and read some post. We are happy to help. We also get a chance to learn from others.

Jack

Layback Bear said:

Welcome to our forum RossESmithIII.

We haven't heard from Dinesh for a while so I will give you a big thank you on his behalf.

Dinesh Last Activity: 20 Oct 2016

Just hang around and read some post. We are happy to help. We also get a chance to learn from others.

Jack

Click to expand...

O come on Jake.. We all learn from you! you know that..