Originally Posted by
MiBz 
There's a much better way, without having to break things up into 2TB LUNs, and you'll also avoid anything to do with WHS's storage pool for Video storage.
Build your new array using 2TB drives.
Remote desktop into WHS, right click on my computer and select manage.
Select Disk Management and you'll see the new array volume which isn't initialized and shows as unallocated.
Right click on the grey area of the volume, intialize as GPT volume.
Format it NTFS |64k clusters | Assign a drive letter above D (ex: R)
Give it a name (ex: RaidStorage)
Exit from Disk Management
Go to My Computer and the R drive now appears as a drive letter.
Open it
Create a new folder, call it Movies or RaidStorage (or whatever you like)
Open the link to WHS's folder shares and right click on the Video share.
Note the share security settings for each group.
Administrators
Creator Owner
RO_5(WHS\\RO_5) - this is the group containing users with read only access
RW_5(WHS\\RW_5) - this is the group containing users with read write access.
System
Now go back to the folder you created on the array drive
Right click, select Share and set the share security to the same as Video noted above.
Now when you access WHS from any network client you will see a shared called Movies (or whatever you called it) that can be accessed same as all other shares.
The additional step to assign the same share rights and groups as WHS's Video folder means that any users you add or changes to those users you make in the WHS console that you give access to Video will also apply to this folder so you'll never need to do it manually.
Last step in remote desktop
Open the WHS shared folder's link and open the Video folder.
In my computer open the drive letter you assigned to the raid array.
Now drag/copy the movies from the WHS Video share to the raid array.
You can also temporarily do the same for all other data that's on the WHS drive pool.
Once the drive pool is empty, you can start removing each 1TB LUN from WHS's disk management, but before you do this make sure you have at least 1 1TB single drive in the drive pool that WHS can move data like client backups to when it prepares to eject the raid LUNs.
At that point you have all your video files safely on the raid array outside the WHS pool and you can still use 2,3,4 x 1TB drives (with duplication on) for your pics, music, documents and whatever else you want.