[Kevin Edwards]

Hi,

I would be grateful if anyone could help me out with this. I was following a guide on installing a dual operating system which required me to use the diskpart utility to shrink a partition and create a new smaller partition (on which the second operating system was to reside). The commands entered were as follows:

>>List disk
>> Select disk [disk #]
>> List partition
>> create partition primary id=af
>> active

After making the changes, I rebooted my system and received the dreaded 'missing operating system' message. I tried using recovery console to no avail. I'm guessing that I need to restore my active partition; unfortunately, I am not the most computer literate person in the world, and would be grateful if someone could provide me with a step-by-step guide to restoring my partition (or whatever is likely to be the problem).

Many thanks in advance,

Kevin Edwards

[Advertisements]

Unfortunately I am not familiar with diskpart. At a guess I would say that your new partition is now the active one. I think you need to be looking for a command to make your OS partition (maybe partition 1 or 2 (if you have a recovery partition)) the active partition. There may be other partitioning software, such as Acronis Disk Director or maybe Gparted that will allow you to do this.

EDIT
Having had a look at Microsoft's diskpart section it seems to me that you need to enter the same commands that you entered before. But when you get to List Partition you need to know which partition your OS is on and then make that one active. If you're not sure I would try 1 less than you used before. ie if you used partition 3 then set 2 to active.

Edited by Quackers88, 13 March 2009 - 06:53 PM.

[Quackers88]

Unfortunately I am not familiar with diskpart. At a guess I would say that your new partition is now the active one. I think you need to be looking for a command to make your OS partition (maybe partition 1 or 2 (if you have a recovery partition)) the active partition. There may be other partitioning software, such as Acronis Disk Director or maybe Gparted that will allow you to do this.

EDIT
Having had a look at Microsoft's diskpart section it seems to me that you need to enter the same commands that you entered before. But when you get to List Partition you need to know which partition your OS is on and then make that one active. If you're not sure I would try 1 less than you used before. ie if you used partition 3 then set 2 to active.

Edited by Quackers88, 13 March 2009 - 06:53 PM.

[Quackers88]

This might do it

Once in diskpart

select disk 0 (probably 0)

list partition xyz (where xyz is your OS partition - it may be obvious by its size, if shown)

active

[Kevin Edwards]

Hi,

Thanks for the quick response; I did a bit of late night web searching and came to pretty much the same conclusion. I've since reset the correct partition to 'active' and have a working computer again!

Best wishes,

Kevin

[Quackers88]

Very nice! Panic over. It's one way to learn things