Author Topic: installed from USB key and cannot boot from HD anymore  (Read 7069 times)

ben

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installed from USB key and cannot boot from HD anymore
« on: June 17, 2009, 23:49:11 PM »
Hi,
first thanks for making this program available.
I am writing because I don't know how to boot any partition of my laptop anymore.
I will explain what was the original configuration, what I planned to achieve, which steps I followed, and what the result now is.

What I had before:
- laptop with 1 HD, 2 partitions. Part1: NTFS (primary) with Windows XP. Part2: NTFS (logical) with only data

What I wanted to do:
- make a dual boot with 2 installations of windows XP. I inspired from the XP-Vista dual boot example of the manual (http://www.plop.at/en/bootmanager.html#ex1).

What I did (something was probably wrong...):
- modified the partitions using a partitioning tool. Part1: unchanged WinXP partition. Part2: copy of Part1 (windows XP). Part3: Data.
- I have no floppy drive on my laptop so I choose the "Harddisk install using DOS" method and created a bootable DOS USB key and copied the "plpinst.com" file on it.
- booted from the USB Key using the BIOS menu
- executed plpinst.com - it turned out the boot manager was installed on the USB Key, not on the Harddrive. I decided to use it anyway and proceed further (create dual boot with hidden partitions)
- Rebooted from the USB Key. Now I can see the PLoP screen. What I can then observe: 2 menu items have been automatically populated, "installed OS 1" actually directs the boot on the USB Kay, starting PLoP again, "installed OS 2" directs to the 1st partition of my HD (win xp starts properly). Furthermore, when I enter linked partitions, I realised HDA is actually the USB Key (1 partition), HDB is my internal HD (3 Partitions).
- configured the 1st profile: all don't touch except  HDB slot 1 (hdb11, pressed b to set boot flag) HDB slot 2 (pressed c to clear the partition).
- select to start the 1st profile -> nothing happens, I get a black screen with a blinking underscore in the up-left corner.

After that I selected to boot directly from the internal harddrive using the BIOS menu, and I get the same black screen and blinking underscore. So I know something was modified was modified on the internal drive preventing it from booting at all - using directly the BIOS of using PLoP.

Can you help me please? What went wrong?
How can I fix my internal drive so it will boot again?

Another info about the current status. I configured the second profile to HDA slot 1 boot and all don't touch. When I select the second slot in PLoP, I get the message "***Warning*** The bootsector is the MBR - Continue boot? [y/n]" When I press Y, then a fresh PLoP menu is displayed again. I don't know how to boot on my USB Key either now...

Thanks in advance for any info/suggestions.
Ben

Elmar

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Re: installed from USB key and cannot boot from HD anymore
« Reply #1 on: June 18, 2009, 13:42:19 PM »
hi,
installing from usb was no good idea.

lets use a slow and secure way to restore all partition infos. go in the boot manager menu at setup/partitions through any partition/view-edit-modify and write down the values of BP and post it.

ben

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Re: installed from USB key and cannot boot from HD anymore
« Reply #2 on: June 19, 2009, 12:55:58 PM »
here are the info:

partitions info in boot manager

hda1
----
BP 00 01 01 00 0C FE 3F 06 - 3F 00 00 00 C1 E4 01 00

P1 same as BP
P2 00 00 etc
P3
P4

hdb1
----
BP 00 01 01 00 07 EF FF FF - 3F 00 00 00 61 00 E2 04

P1 81 01 01 00 07 EF FF FF - 3F 00 00 00 61 00 E2 04
P2 00 EF FF FF 07 EF FF FF - A0 00 E2 04 61 00 E2 04
P3 00 EF FF FF 0F EF FF FF - 40 01 C4 09 90 40 58 13
P4 00 00 etc

hdb2
----
BP 00 EF FF FF 07 EF FF FF - A0 00 E2 04 61 00 E2 04

P1 to P4: same as for hdb1

hdb3
----
BP 00 EF FF FF 0F EF FF FF - 40 01 C4 09 90 40 58 13

P1 to P4: same as for hdb1


Am I anywhere near the truth when I suspect the trouble comes from the fact that the HD is detected by PLoP as the second HD, and it sets the boot flag as 81h which should be 80h for the 1st HD?

Thanks,
Ben

Elmar

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Re: installed from USB key and cannot boot from HD anymore
« Reply #3 on: June 19, 2009, 16:02:43 PM »
you are right. when you boot with usb then the bios gives the usb device the number 80h and the first internal harddisk gets 81h. when you boot without usb then the first internal harddisk is 80h, but the boot manager wrote 81h as boot flag and in the case without usb its wrong.

lets change the values in the mbr

to make harddisk bootable again:
go to the partition setup of hdb1. write 80 to the first entry of P1.
P1 80 01 01 00 07 EF FF FF - 3F 00 00 00 61 00 E2 04

if you boot without usb, then the harddisk boot should work again


make the usb stick bootable again:
go to the partition setup of hda1. write 80 to the first entry of P1.
P1 80 01 01 00 0C FE 3F 06 - 3F 00 00 00 C1 E4 01 00


ben

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Re: installed from USB key and cannot boot from HD anymore
« Reply #4 on: June 21, 2009, 00:27:17 AM »
Good News !!!
I can actually boot my computer again. THANKS !!!

I have some follow-up questions though:
1 - PLoP got installed on the USB Key. When booting from the key, the Bios makes it look as the first HD of the system. Why can I not then use the boot manager to start XP on the first partition of the  internal HD, which is identified as second HD? The 81h flag on the first partition should allow it to boot, shouldn't it?

2 - I want to be able to undo the installation of the boot manager, that was the reason for creating a bootable USB Key and using the DOS installation method since I don't have a floppy drive. The plpback.bin file is 32K long or 63 sectors of 512 bytes. Which data are saved in this backup file? It doesn't seem to match the first 63 sectors of my USB key before the install. Can you tell me where does the boot manager install itself? I plan to do a manual backup of the sectors using dd.

3 - my next installation option would be the Windows boot menu - would you agree?
Thanks
Ben

Elmar

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Re: installed from USB key and cannot boot from HD anymore
« Reply #5 on: June 21, 2009, 10:36:13 AM »

Quote
1 - PLoP got installed on the USB Key. When booting from the key, the Bios makes it look as the first HD of the system. Why can I not then use the boot manager to start XP on the first partition of the  internal HD, which is identified as second HD? The 81h flag on the first partition should allow it to boot, shouldn't it?

its a windows xp problem. it seems, the loading of ntldr from the second harddisk is not supported. if you have  pc with two empty harddisks and you are going to install xp on the second harddisk, then the xp installer will tell you that a boot partition on the first harddisk is required.

Quote
2 - I want to be able to undo the installation of the boot manager, that was the reason for creating a bootable USB Key and using the DOS installation method since I don't have a floppy drive. The plpback.bin file is 32K long or 63 sectors of 512 bytes. Which data are saved in this backup file? It doesn't seem to match the first 63 sectors of my USB key before the install. Can you tell me where does the boot manager install itself? I plan to do a manual backup of the sectors using dd.

the bootmanager is installed to the first 63 sectors of your harddisk. so plpback.bin is the file with the 63 sectors before installing the boot manager. maybe the data on the usb key looks different as you expected?

Quote
3 - my next installation option would be the Windows boot menu - would you agree?

yes, i agree.
it should not be required to make a backup, but make one with dd and store it on a usb device. thats the safest way.

best regards
elmar