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today i tried to install win7 from an external hdd to my system. i tried this tut and everything went fine till i pluged off the external hdd. after i pluged it off and tried to restart the system i get a missing boot manager error. if i plug the external hdd in again it's all working fine again.

i've searched for the last 2h and didn't find a good answer. did any of you have one ?

regards Alex

ps: i already tried any forms of reperation and the system is installed on the correct hdd.

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What netbook do you have? On your HDD, do you have an exact copy of a valid Windows install disk? – Usta Jun 23 '12 at 3:52
not a notebook -> workstation. it's a valid image i'd unpacked (as said in description) and moved at the hdd – Alex Jun 23 '12 at 3:58
What is your computer model? Because that makes a difference on what key you would press to bring up a menu.... Do you either have the DVD you can stick in the drive, or a 4 GB or larger thumb drive? (And sorry, I was looking at something else about that whole netbook thing... ;) ) – Usta Jun 23 '12 at 4:00
it's self builded ... it's not a comon model ... mainboard: asus rampage extrem and it's an AMI bios. but i don't think it's a hardware / bios prob. i thinks it's belong the the instalation from the external hdd – Alex Jun 23 '12 at 4:03
I'm working on writing an answer. Do you know how to choose a custom boot device? – Usta Jun 23 '12 at 4:05

The issue is boot manager is stored on the wrong drive. To fix this you need the install files on a disk other then that HDD (Either a thumb-drive or a DVD)

1) Unplug your external drive 2) If you have the disk, stick it in the drive and boot from it. 2B) If you don't have a disk, copy to USB flash drive and boot from that 3) When prompted, press key to boot from disk 3B) If prompted, choose your language and keyboard layout 4) type "Bootrec.exe /FixMBR" without quotations and press enter 4B) When that finishes type 'bootrec.exe /FixBoot" and press enter

You might also try "Bootrec.exe /RebuildBCD" if those two don't fix it

Typing Bootrec.exe /? will give you examples and help (You can place /? after any command in Command prompt to show help information and typically a couple of examples


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first of all, thanks for your suggestion. i'll try it asap. but in the meantime i think i've found an other point. win7 always creat a 100mb partition for system requirements. if i've pluged in the external hdd this is used for that partition. but i don't know on how to change this to use the 100mb for system needs. – Alex Jun 23 '12 at 4:31
Good point. To access that, open disk manager (Type Disk manager in the start menu. It should show "Create and format hard disk partitions") Right click "SYSTEM Reserved" and select 'change drive letter and paths' and assign it a drive letter. This will allow you to see the drive in Computer. You might try just copying it over and seeing what happens.... – Usta Jun 23 '12 at 4:41
that's what i tried and it failed. i think i just do it the "old" way and burn it to dvd. – Alex Jun 23 '12 at 4:56
I think the bootmgr includes hardware IDs etc that would prevent it from being directly copied – Usta Jun 23 '12 at 15:21

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