You will now receive a diskpart-prompt:
Diskpart>

Now type “san”. This will provide you with the current configured SAN policy:

SAN Policy : Offline Shared


In the diskpart-prompt, type “san policy=OnlineAll”.
This will result in the following message:
Diskpart successfully changed the SAN policy for the current operating system.

Now type “list disk”, which will give this message:
Disk ### Status Size Free Dyn Gpt
Disk 0 Online 30 GB 0 B
Disk 1 Offline 50 GB 1024 KB

In my case, disk 1 was offline so I typed “select disk 1” which provided:
Disk 1 is now the selected disk

Now type “attributes disk clear readonly”.
Disk attributes cleared successfully.
And to check if all the settings are now correct, type “attributes disk”.
This will give an output something like:
Current Read-only State : No
Read-only : No
Boot Disk : No
Pagefile Disk : No
Hibernation File Disk : No
Crashdump Disk : No
Clustered Disk : No

After the last check has been successful, type “online disk” to bring the disk online.