Help! Dual boot pc not booting.

  computerdiv 21:46 07 Jan 12

Dear forum. I have a problem booting my pc. I have win 7 on 500gb and win xp on 1tb hdd installed and another 1tb hdd. Neither o/s will boot up. Running 8800 gtx 2.4ghz quad core pentium 6600. When I boot I get the mobo (ASUS PK7) flash up and can access the bios. If I try to boot straight from win 7 I get a cursor that flashes eternally. I don't get a choice to boot from either o/s. My first guess was that I had fried my pentium chip but as I seem to be prompted to install windows or repair it with the dvd I now think it is ok. When I tried to repair win 7 o/s using the dvd the disc promted me to choose an o/s to repair but no o/s appeared in the window to choose from. I removed each hdd and tested them on my laptop with a dock and the xp and win 7 hdd seemed ok. I could not see the apps on the other hdd so maybe I have a problem with that hdd. I have tried to boot from both o/s 1 at a time and still have no o/s to boot from.

can any one give some advice as to what might be wrong.

  robin_x 22:33 07 Jan 12

See if you can get the Repair options when you repeatedly press F8 on boot (although they may be the same as when you tried from DVD)

  robin_x 22:36 07 Jan 12

Make sure you haven't got any flash sticks/memory cards left in any slots or a disc in the optical drive of course.

  computerdiv 19:42 11 Jan 12

Ok I think my boot log has gone for a burton. I have tried bootrec/fixmbr but bootrec/fixboot doesn't work. Can someone help with Diskpart please

  robin_x 20:57 11 Jan 12

Try Partition Wizard Bootable CD

(burn on your laptop)

It has an Update MBR facility too. Although I have never used that on a dual boot machine.

  robin_x 21:01 11 Jan 12

edit: Rebuild MBR facility

  c4rm0 21:05 12 Jan 12

Rather than trying to repair the MBR/Boot sector i would try recreate the BCD store completely

Boot to Windows PE via your Windows 7 disk and at the command prompt type the following

bcdedit /export C:\BCD_Backup c: cd boot attrib bcd -s -h -r ren c:\boot\bcd bcd.old bootrec /RebuildBcd

then reboot

  computerdiv 00:32 17 Jan 12

I have recovered win 7 installation now thanks to a post I found about going to full install option and then going back a step to repair option to get a hdd option in system recovery window. I then just did a normal recovery and all ran OK. thank you for every bit of help offered.

I now have a new problem concerning my win xp installation.

When I had no O/S system booting I made a new partition using a laptop and dock on win xp hdd to try to install a new win 7 O/S if needed. As it happened I recovered the win 7 O/S before needing to do that. After booting in to win 7 and exploring my hdd I no longer had the win xp O/S as an option and the hdd is only showing as being 64GB in size instead of 1Tb. So can you please tell me how I can recover the win xp installation?

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