How to add a missing drive on Windows Server

Learn how to detect, initialize, and mount unallocated drives using Disk Management in just a few simple steps.

Key points to consider

• Newly added drives on Windows Server may appear as offline, unallocated, or not initialized. These must be manually configured using the Disk Management utility.

• During initialization, you will be prompted to select a partition style:

  • MBR (Master Boot Record) – recommended for drives under 2TB or when legacy BIOS compatibility is required.

  • GPT (GUID Partition Table) – required for drives over 2TB, and preferred for modern systems using UEFI firmware.

  • If you are unsure which option to choose, you can always contact the Cherry Servers support team for assistance at support@cherryservers.com.

• Once the disk is initialized, you will need to create a new volume, assign a drive letter, and format the drive (typically with NTFS) to make it usable.

• After setup, the drive will appear under This PC in File Explorer and can be used immediately.

Introduction

In some cases, when you deploy a Windows Server instance or attach a new disk, the drive may not appear automatically under "This PC". This does not necessarily mean the disk is broken or misconfigured, it simply needs to be initialized and formatted before the operating system can use it.

In this tutorial, we will walk you through the process of detecting, initializing, partitioning, and formatting a new drive on Windows Server using the built-in Disk Management utility. Whether you are adding a secondary storage disk, preparing a volume for backups, or setting up an additional data partition, these steps will help you get the job done reliably.

Step-by-Step Instructions

Step 1: Open the Disk Management utility

Once your additional drive is physically attached to the Windows Server (whether via virtualization or direct hardware connection), the next step is to access the Disk Management utility, which allows you to manage all connected storage devices.

To open Disk Management, follow these steps:

1. Right-click on the Start menu (or press Win + X on your keyboard).

2. From the context menu, select Disk Management (see Fig. 1).

   
   Fig. 1. Opening Disk Management by right-clicking the Start button and selecting "Disk Management" from the menu.

3. Alternatively, you can press Win + R to open the Run dialog box, type diskmgmt.msc, and press Enter (see Fig. 2).

   
   Fig. 2. Opening Disk Management via the Run dialog by entering diskmgmt.msc and clicking OK.

The Disk Management window will now launch, displaying a list of all currently attached storage devices. These include system drives, data partitions, and any newly connected disks (see Fig. 3).

Fig. 3. In Disk Management, the second disk (Disk 1) appears as Unknown and Unallocated. This indicates that the drive is detected by the system but not yet initialized or ready for use.

What to expect:

• If the new disk has never been initialized, it will appear in the bottom panel as “Disk 1” (or another number), marked as “Unknown” and “Not Initialized”.

• It may also be labeled as “Unallocated”, meaning no partitions have been created yet (see Fig. 4).

  
  Fig. 4. Highlighted view of Disk 1 showing the Unallocated space, indicating that the drive must be initialized before it can be used.

• In some cases, the disk may appear as "Offline", and you will need to right-click on the disk label and select "Online" before proceeding (see Fig. 5).

  
  Fig. 5. To activate the new disk, right-click on the offline drive and select Online to make it available for initialization and formatting.

Step 2: Initialize the disk

Once the new disk has been brought online, it still cannot be used until it is initialized. Initialization is a necessary process that prepares the drive to be formatted and written to by Windows. Without initialization, the system will not recognize the disk for storage purposes, even if it appears in Disk Management.

After bringing the disk online, it will now show a status of “Not Initialized” (see Fig. 6). At this point, you need to define a partition style before continuing. This is where you choose between the MBR (Master Boot Record) and GPT (GUID Partition Table) schemes.

Fig. 6. The newly online disk appears as “Not Initialized” in Disk Management and must be initialized before use.

To begin initializing the disk, follow these steps:

1. In the Disk Management window, right-click on the newly online disk that says “Not Initialized”.

2. From the context menu, select Initialize Disk (see Fig. 7).

   
   Fig. 7. To initialize the disk, right-click on the uninitialized drive and select "Initialize Disk" from the context menu.

Yo will now see a dialog box prompting you to select the partition style (see Fig. 8). If your drive is larger than 2TB, you must choose GPT, as MBR does not support partitions beyond that size. GPT is also a preferred option for modern systems with UEFI firmware. However, if you are working with older systems or drives smaller than 2TB, MBR might be more compatible.

Fig. 8. Selecting the partition style for the new disk.

If you are unsure which partition style to use or what best fits your server configuration, you can always contact our support team at support@cherryservers.com, we will be happy to assist you in making the right choice for your use case.

Once you have selected your preferred partition style, click OK to proceed (see Fig. 9). The disk is now initialized and ready to be formatted and partitioned in the next steps.

Fig. 9. Initialize the disk by selecting it (1), choosing the appropriate partition style, MBR or GPT (2), and clicking “OK” to confirm (3).

Step 3: Create a New Volume and format the Drive

Once the disk is initialized, it will appear as Unallocated space in Disk Management. In order to use this storage, you must now create a new volume and format it with a file system (typically NTFS). This process will make the drive visible and usable in Windows.

1. Right-click the unallocated space on the new disk.

2. From the context menu, select New Simple Volume... to launch the volume creation wizard (see Fig. 10).

   

   Fig. 10. Right-click the unallocated space on the new disk and select New Simple Volume... to begin creating a usable partition.

   This New Simple Wizard (see Fig. 11) will guide you through the configuration process for the new volume, allowing you to specify the size, assign a drive letter, and format partition.

   
   Fig. 11. The New Simple Volume Wizard welcome screen appears. Click Next to begin the volume creation process.

3. Specify volume size – you can accept the maximum available space or adjust it based on your needs. Most users should use the full capacity (see Fig. 12).

   
   Fig. 12. Specify the volume size. By default, the wizard selects the maximum available space. Click Next to continue.

4. Assign a drive letter – choose a letter (such as D: or E:) that is not already in use by other drives. This will be how the new volume appears in File Explorer (see Fig. 13).

   
   Fig. 13. Assign a drive letter to the new volume. The default selection is usually appropriate, but you can choose a different letter if needed. Click Next to proceed.

5. Format the partition – choose the file system (typically NTFS) and allocation unit size (leave as Default unless you have specific requirements). You may also provide a volume label (like “Data” or “Backup”) (see Fig. 14).

   
   Fig. 14. Format the new partition using your preferred settings. NTFS is the recommended file system for Windows. Optionally, set a custom volume label (e.g., “Storage”).

6. Enable Quick Format – leave this box checked unless you require a full format for data wiping purposes (see Fig. 15).

   
   Fig. 15. Ensure “Perform a quick format” is checked for faster setup, unless a full scan is required. Then click Next to proceed to the final step.

7. Finish the wizard – click Finish to apply all settings. Windows will format the new partition and it will be ready for use in a few seconds (see Fig. 16).

   
   Fig. 16. Review your selected volume settings and click Finish to complete the New Simple Volume Wizard and create the partition.

Once formatting is complete, the volume status should show as Healthy (Primary Partition) (see Fig. 17), and the drive will appear in File Explorer (see Fig. 18), ready to store files.

Fig. 17. The new volume Storage (D:) has been successfully created and formatted. It now appears in Disk Management as a healthy primary partition, ready for use.

Fig. 18. The newly added Storage (D:) drive is now visible in File Explorer under “This PC,” confirming that the setup and formatting process was completed successfully.

Note: in rare cases, if you don not see the drive immediately, rebooting your server can help Windows refresh its volume table and display the new drive correctly in the system.

Summary

In this tutorial, you have learned how to add and initialize a missing disk on a Windows Server using the built-in Disk Management tool. This is a common task when deploying servers with additional storage that does not appear by default in the system.

We started by identifying the missing drive through Disk Management and bringing it online. Once online, we demonstrated how to initialize the drive by selecting the appropriate partition style, either MBR for disks smaller than 2 TB, or GPT for larger or modern systems. We also explained when to use each format and recommended reaching out to our support team at support@cherryservers.com if you are unsure which to choose.

After initializing the disk, we guided you through creating a new simple volume, assigning it a drive letter, formatting it with the NTFS file system, and completing the wizard. Finally, we verified that the new volume appears correctly in File Explorer and is ready for use.

By following this guide, you can ensure that your server fully recognizes and utilizes all connected storage devices, improving operational reliability and resource efficiency.