The disk is offline because it has a signature collision with another disk that is online 1
Recently, we cloned a hard disk using dd.
When we booted into Windows, the new drive was not visible.
After checking with the disk utilities, we got the following informative message:
The disk is offline because it has a signature collision with another disk that is online
To resolve the issue, we used diskpart.
To start diskpart, press the key combination Win + R which will pop up the Run prompt.
Type diskpart in the input box and hit the Enter key.
A new terminal window will appear.
Using that we identified the two disks and changed the label for the second one.
First step:
We issued list disk to get the list of disks.
DISKPART Microsoft DiskPart version 10.0.14393.0 Copyright (C) 1999-2013 Microsoft Corporation. On computer: BYTEFREAKS-NET DISKPART> list disk Disk ### Status Size Free Dyn Gpt -------- ------------- ------- ------- --- --- Disk 0 Online 931 GB 0 B Disk 1 Offline 465 GB 0 B
Second step:
We issued select disk 1 so that we could process the disk 1 that was offline and using uniqueid disk we got the signature of the disk.
DISKPART> select disk 1 Disk 1 is now the selected disk. DISKPART> uniqueid disk Disk ID: 09FC13CB
Third step:
Set the signature of the disk to a random value other than the one that it already had using the command uniqueid disk ID=FFAABBCCDD
DISKPART> uniqueid disk ID=FFAABBCCDD DISKPART> uniqueid disk Disk ID: FFAABBCCDD
The random value must be 8 characters long and each character must be a value between 0-9 or A-F.
Finally:
Restart the machine to get both disks running.
