How to Initialize an SSD in Windows 11

To initialize a new SSD in Windows 11, right-click the Start button, choose Disk Management, right-click the new disk (it shows Not Initialized), choose Initialize Disk, keep GPT selected, and click OK. Then right-click its Unallocated space, choose New Simple Volume, and finish the wizard so the drive gets a letter and shows up in File Explorer.

These steps work on Windows 11 24H2 and 25H2 and are the same on Windows 10. They apply to internal NVMe and SATA SSDs, hard drives, and most external drives. You need an administrator account.

Only initialize a new, empty drive. Initializing erases whatever is on the disk. If a drive that used to hold files suddenly shows Not Initialized or RAW, don’t initialize or format it; that’s a data-recovery problem, and initializing will make recovery harder.

Before You Start

• Install the drive first. Fit the SSD with the PC shut down and unplugged, following your PC or motherboard manual. M.2 slots support NVMe, SATA or both, so check that the drive matches the slot.
• Note the drive’s capacity. You’ll use it to pick the right disk in Disk Management. The new drive isn’t always Disk 1.
• Check whether it already works. Many external SSDs come formatted. Open File Explorer > This PC. If the drive is listed with a letter, it’s ready to use and you can skip this guide.

Step 1: Open Disk Management

1. Right-click the Start button (or press Windows + X).
2. Click Disk Management. A window opens with a list of volumes at the top and a map of every disk at the bottom.
3. If Windows shows an Initialize Disk dialog right away, it has already found the new drive. Go to step 4 of the next section.

You can also press Windows + R, type diskmgmt.msc, and press Enter. If you get a permission error, search Start for Computer Management, right-click it, choose Run as administrator, and then open Storage > Disk Management.

For every other route, including Search and Task Manager, read about opening Disk Management in Windows 11.

Step 2: Initialize the Disk

1. In the lower pane, find the disk whose gray label on the left says Unknown and Not Initialized, with a black bar labeled Unallocated next to it. Check that its size matches your new SSD. (A 1 TB drive shows as about 931 GB because Windows counts in binary units.)
2. If the label says Offline instead, right-click the label and choose Online first.
3. Right-click the gray disk label (not the black bar) and choose Initialize Disk. A dialog opens with the disk checked.

4. Make sure only the new disk is checked, and leave GPT (GUID Partition Table) selected.
5. Click OK. The label changes to Basic and Online. The space still shows as Unallocated, which is expected.

At this point the drive is initialized but not usable yet. It needs a volume.

To split the drive into more than one volume, follow the steps for partitioning a hard drive on Windows 11.

Step 3: Create a Volume and Assign a Drive Letter

1. Right-click the black Unallocated bar on the new disk and choose New Simple Volume. The New Simple Volume Wizard opens. Click Next.

2. Leave the volume size at the maximum shown to use the whole drive, then click Next. Enter a smaller number only if you want to split the drive into more than one volume.
3. Choose a drive letter from the menu (Windows suggests the next free one), then click Next.
4. On the Format Partition screen, set File system to NTFS, leave Allocation unit size at Default, and type a name in Volume label, such as Data SSD. Leave Perform a quick format checked. Click Next.

5. Review the summary and click Finish. After a few seconds the bar turns blue and shows the label, letter and Healthy (Primary Partition).
6. Open File Explorer > This PC. The new drive appears under Devices and drives and is ready for files.

Microsoft documents the same process in its guide to initializing new disks, which applies to Windows 11 and Windows 10.

If the new drive will hold private files, you can encrypt it with BitLocker in Windows 11 once it has a drive letter.

To have Windows put new documents, photos or apps on the new drive, change the default save location in Windows 11.

Once the new SSD has a drive letter, you can move your Dropbox folder to it from Dropbox Preferences.

Bought two new drives so one can protect the other? Follow the steps for setting up RAID in Windows 11 with a Storage Spaces mirror.

GPT or MBR: Which Should You Choose?

Choose GPT for almost every SSD in a Windows 11 PC. It’s the default, it supports drives larger than 2 TB, and it’s required for a drive that will boot Windows 11 on a UEFI PC.

MBR is an older style. Pick it only if you’ll move the drive to an old computer that doesn’t support GPT. If you chose the wrong one on an empty drive, delete the volume, right-click the disk label, choose Convert to GPT Disk (or Convert to MBR Disk), and create the volume again.

Format Options for Different Uses

How you’ll use the drive	File system	Why
Storage inside a Windows PC	NTFS	Full Windows support, no file size limit that matters
External drive shared with a Mac	exFAT	Windows and macOS can both read and write it
Small USB drive for older devices, TVs, or game consoles	FAT32	Works almost everywhere, but Disk Management only offers it for volumes of 32 GB or smaller, and single files are capped at 4 GB

If you need FAT32 on a larger drive, read about the workarounds for formatting a USB drive to FAT32 in Windows 11.

Initialize a Disk From Settings Instead

Windows 11 can also set up a new drive without Disk Management.

1. Open Settings > System > Storage.
2. Click Advanced storage settings, then Disks & volumes.
3. Find the new disk, which shows as not initialized, and click Initialize. Keep GPT and click Initialize again.
4. Click Create volume on the unallocated space, enter a label, choose a letter and NTFS, and click Format.

Both tools do the same thing, so use whichever you find easier.

Troubleshooting

The new SSD doesn’t appear in Disk Management

Click Action > Rescan Disks. If it’s still missing, shut down and check that an M.2 drive is fully seated and screwed down, or that a SATA drive has both its data and power cables attached. Check that your PC’s firmware (BIOS/UEFI) lists the drive. For an external SSD, try another USB port directly on the PC and a different cable. For more external-drive checks, read about fixing a USB drive that isn’t showing up.

Initialize Disk is grayed out or missing

The disk is probably already initialized. If it shows Online with Unallocated space, skip to creating a volume. Some USB drives can’t be initialized at all; for those, just create a volume or format the drive.

Initialization fails with an I/O device error

Try a different port or cable, and for an internal drive, a different M.2 slot or SATA port. An enclosure or adapter that doesn’t support the drive can also cause this. If the drive fails in two ports, contact its maker; it may be faulty.

The drive has a volume but no letter

Right-click the volume, choose Change Drive Letter and Paths, click Add, pick a letter, and click OK. For more detail, read about changing a drive letter in Windows 11.

Frequently Asked Questions