Why can’t I boot a laptop from a USB disk?

Avoriaz

I have a new Acer 8935g laptop with Windows 7.

I have the disk from my retired Dell XP laptop in a USB caddy.

I’ve tried booting the Acer from the XP disk via USB. It has the capability to boot from a USB drive.

I’ve done all the obvious.

F2 to change boot order so that USB HDD is first: It just boots from the internal 7 disk.

F12 to select boot: The USB drive doesn’t show as an option.

When I power on, the light on the USB caddy comes on immediately so I know it is being powered from the motherboard.

Why isn't the USB drive being seen?

Any suggestions?

Thanks

mongoose2009

i would say at a guess the usb would have to be formatted FAT32 for it to boot

i have booted linux off a usb stick but not XP

spud17

I have the disk from my retired Dell XP laptop in a USB caddy.

You can't just swap an HD and expect it to boot, drivers and mbr for starters.

henrysprings

Might be the usb drivers

tomsolomon

Try booting from your Win XP disc.
See if it detects the USB drive as an OS and repair the MBR, might work......

debitcardmayhem

spud17 wrote: »

You can't just swap an HD and expect it to boot, drivers and mbr for starters.

henrysprings wrote: »

Might be the usb drivers

Avoriaz wrote:

F2 to change boot order so that USB HDD is first: It just boots from the internal 7 disk.

F12 to select boot: The USB drive doesn’t show as an option.

Edit Just posted after Tom's post he has a very good point

Delete the BIOS entry from Boot entry for Internal Disk and just leave it as USB only, If Boot fails and it is drivers then you should get a message I would have thought but I don't know much about Acers.

debitcardmayhem

tomsolomon wrote: »

Try booting from your Win XP disc.
See if it detects the USB drive as an OS and repair the MBR, might work......

Following on from this if you have a Win 7 repair disk then try booting that and select repair, see if it can find the XP system, if so it should put the XP system in the BCD entry on W7 so that you have the choice from normal boot, thats what I have on my 7/XP system, albeit on the same disk, not on a USB.

Avoriaz

spud17 wrote: »

You can't just swap an HD and expect it to boot, drivers and mbr for starters.

I'm not expecting it to boot perfectly. I was expecting it to boot with just basic drivers.

The Acer is making no attempt to boot from a USB device. It appears not to even see the attached USB disk.

Avoriaz

tomsolomon wrote: »

Try booting from your Win XP disc.
See if it detects the USB drive as an OS and repair the MBR, might work......

Excellent idea thanks.

I will try that tomorrow and post again.

Avoriaz

debitcardmayhem wrote: »

Following on from this if you have a Win 7 repair disk then try booting that and select repair, see if it can find the XP system, if so it should put the XP system in the BCD entry on W7 so that you have the choice from normal boot, thats what I have on my 7/XP system, albeit on the same disk, not on a USB.

Thanks.

I will try that if Tom's idea doesn't work.

IcyEars

Is the USB disk actually bootable? There is a boot flag in the MBR (I think?) that tells the BIOS that the disk is bootable. If this isn't set then the computer won't see it to boot from it.

Might be worth checking this is set.