How can i make/install windows 7 using my external hard drive ?

bootsect /nt60 E: /force /mbr =>this rewrites the mbr (master boot record) of the physical disk where partition E is on. When booting from that drive it reads the code which searches for an active partition which is E. Then it loads the boot sector of E.

bootsect /nt60 E: /force => this rewrites the boot sector of E-partition. /nt60 means vista/win7 style. The win7 boot sector has code in it that says ... run bootmgr. bootmgr loads the boot menu e:\boot\bcd and displays all configured Operating systems in that menu. There's only one (the installation) so it starts immediately

Try to start from external usb drive now. Tap F8 a lot of times during boot, so you see a bootmenu. Does that work? Are you very sure it tries to boot from usb?

so it doesn't start from usb. remove harddisk from "boot device" in bios. just for test. what happens when you reboot afterwards? tap f8.

so usb is on top of "boot devices" in bios. HDD can't be removed from list are replaced by another option.
boot from usb (try to) and tap f8 so you see the menu.

Do you see any installations so does a menu appear? or only safe mode, normal etc?
try normal. does that start winxp or win7 install?

This it should say (sorry it's in dutch)

Code:

D:\>bootsect /nt60 c: /force
Target volumes will be updated with BOOTMGR compatible bootcode.
C: (\\?\Volume{d2602ac2-ded6-11e0-a821-806e6f6e6963})
    Updated NTFS filesystem bootcode.  The update may be unreliable since the
    volume could not be dismounted during the update:
        Toegang geweigerd. (means access denied)
Bootcode was successfully updated on all targeted volumes.
-------------------------------------------------------------
D:\>bootsect /nt60 c: /force /mbr
Target volumes will be updated with BOOTMGR compatible bootcode.
C: (\\?\Volume{d2602ac2-ded6-11e0-a821-806e6f6e6963})
    Updated NTFS filesystem bootcode.  The update may be unreliable since the
    volume could not be dismounted during the update:
        Toegang geweigerd. (means access denied)
\??\PhysicalDrive0
   Successfully updated disk bootcode.
Bootcode was successfully updated on all targeted volumes.
D:\>

Did you get Bootcode was successfully updated on all targeted volumes. at first command?
Did you get
\??\PhysicalDrive0
Successfully updated disk bootcode.
Bootcode was successfully updated on all targeted volumes.
on second command?

Of course do it for E instead of C

Target volumes will be updated with BOOTMGR compatible bootcode.
E: (\\?\Volume{d2602ac3-ded6-11e0-a821-806e6f6e6963})
Forced dismount complete, open handles to this volume are now invalid.
Successfully updated NTFS filesystem bootcode.
Bootcode was successfully updated on all targeted volumes.

This is the message you should get