GPT Disk Question

[Yoko Ono]

Hi all I have a GPT protected disk from my laptop that I want to scan for viruses, I usually just put it in my desktop but with this new Windows 8 pc I have the disk manager in my Windows 7 64 bit machine is asking me to initialize the disk to either MBR or GPT. If I initialize the disk on my Windows 7 desktop with GPT will I be able to boot from it when I reinstall it in my Windows 8 laptop?

[jaclaz]

Wait a minute.

If the disk is to be initialized, it means that - as is - it contains NO accessible data (and as such it makes very little sense to scan it for viruses).

On "normal" MBR type of disks the "initialize this disk" is triggered by the absence of the "Magic Bytes" 55AA at offset 510 in first sector (the MBR).

What the Disk Manager does when you go on is simply to write to the MBR the (specific OS) MBR code (including the Magic Bytes).

There is no "difference" (in the sense of "substantial" difference) between the 7 and 8 MBR code, for "normal" booting, BUT there may be incompatibilities if bitlocker and/or hybrid boot is used, AND since you mention a laptop, remember that a number of OEM's use a "special" MBR to give the user the possibility of using the "recovery" partition.

I think that thee are no particular issues in using (running on 7) the windows 8 version of bootsect.exe (which has a switch to operate on the MBR too), but the basic issue remains that if the disk was not "wiped" (or damaged) it should NOT need to be initialized.

Additionally (and specifically to GPT disks) the status of possible incompatibilities between 7 and 8 (possibly only when AF or 4k sectored disks are involved) is not entirely clear, see:

http://www.forensicfocus.com/Forums/viewtopic/t=11431/start=14/

jaclaz

[Tripredacus]

I agree, if Disk Management is prompt to format the disk then something is off with it. I would put it back into the Windows 8 notebook and make sure it works. The prompt you would want to be seeing is to import a foreign disk.

[dencorso]

If I initialize the disk on my Windows 7 desktop with GPT will I be able to boot from it when I reinstall it in my Windows 8 laptop?

No. If you let Windows 7 initialize the disk, *all* its contents will be lost, so, if it is working, as I understand it is, whatever you do, do not initialize it!