Add and format a new disk in Windows Server Disk Management

When extra storage is attached to a Windows Server VPS, it appears as an offline, unallocated disk. It needs to be brought online, initialised and formatted before you can use it. This takes a couple of minutes in Disk Management.

Before you start

• An RDP session as an administrator.
• The new disk attached to your VPS. If your existing C: drive was enlarged instead, follow extend a disk in Disk Management.

Open Disk Management

Right-click Start → Disk Management, or press Win+R and run diskmgmt.msc.

Bring the disk online and initialise it

1. If the new disk shows Offline, right-click its label on the left and choose Online.
2. Right-click it again and choose Initialize Disk.
3. Select GPT (GUID Partition Table) and click OK. GPT supports disks over 2 TB.

Create and format a volume

1. Right-click the Unallocated area and choose New Simple Volume.
2. Keep the maximum size, choose a drive letter (for example D:).
3. File system NTFS, allocation unit Default, add a label such as Data, tick Perform a quick format.
4. Click Finish. The drive appears in File Explorer.

Do it with PowerShell

Get-Disk | Where-Object PartitionStyle -eq "RAW"

Initialize-Disk -Number 1 -PartitionStyle GPT
New-Partition -DiskNumber 1 -UseMaximumSize -DriveLetter D | Format-Volume -FileSystem NTFS -NewFileSystemLabel Data

Replace 1 with the number the first command shows. More commands in PowerShell essentials.

Check afterwards

• The disk shows Online and the volume Healthy.
• Move data folders (backups, databases, uploads) to the new drive and update app paths.

Troubleshooting

• Disk not listed: choose Action → Rescan Disks, or restart the VPS.
• The disk is offline because of a policy: run Set-Disk -Number 1 -IsOffline $false.
• Disk read-only: Set-Disk -Number 1 -IsReadOnly $false.

Next steps

• Extend C: after a disk upgrade
• Back up Windows Server
• Monitor CPU, RAM and disk