AOMEI Partition Assistant
[3 Methods] How to Fix Drive Letter Changed By Itself on Windows 11, 10, 8, 7?
When the driver letter changed by itself, you can read this tutorial to know why it happens and how to fix it. There are 3 fixes can help you effectively solve the problem.
By Irene / Updated on April 2, 2025
Why did my drive letter change by itself?
Drive letters act like labels that help Windows identify your storage devices. Each disk or partition is given a unique letter (like C: or D:). But sometimes, you might notice your drive letter suddenly changes on its own—for example, after restarting your computer or plugging in an external drive. If you’re facing this issue, don’t worry. Understanding why it happens is the first step to fixing it. Why did your hard driver change letters by itself?
| Reason | Explanation | Possible Solutions |
|---|---|---|
| External Drive Reassignment | Windows may assign a different letter if another device is plugged in first. | Disconnect unnecessary external drives before restarting. |
| Drive Disconnection | If an external drive is removed and reconnected, Windows may assign a new letter. | Manually reassign the drive letter in Disk Management or AOMEI Partition Assistant. |
| System Updates or Restart | Updates or reboots can cause Windows to change drive letters. | Reassign the drive letter manually in Disk Management. |
| New Drive Installation | Adding a new HDD, SSD, or USB may shift existing drive letters. | Assign static drive letters to main disks in Disk Management. |
| Corrupted Volume Information | Damaged partition data may cause drive letter changes. | Run CHKDSK /F or use AOMEI Partition Assistant to repair partitions. |
Below, we will share easy-to-follow solutions to resolve or prevent drive letter changes.
How to fix drive letter changed by itself
Here are 4 solutions for fixing driver letter changed by itself. You can follow to fix the issue.
Fix 1. Change the drive letter back
If your drive letter changes unexpectedly due to a Windows update or system error, you can easily restore it using Disk Management. Here’s how:
Step 1. Open Disk Management – Right-click the Start button and select Disk Management. Locate the Drive – Find the affected partition, right-click it, and choose Change Drive Letter and Paths.
Step 2. Reassign the Drive Letter – Click Change, select a new letter from the drop-down menu, and click OK to confirm.
If Disk Management does not save the changes, or you encounter drive letter is not available in Disk Management, you may find it helpful to use a third-party tool like AOMEI Partition Assistant. It provides a simple and reliable way to manage drive letters smoothly.
This versatile partition management tool allows you to easily change drive letters, modify partition type IDs, and perform other disk operations such as resizing, moving, merging, and formatting partitions. With its user-friendly interface, you can make these changes in just a few clicks. It is compatible with all Windows versions, including Windows 11, 10, 8.1, 8, 7.
To reassign a drive letter using AOMEI Partition Assistant, simply download the software and follow these steps:
AOMEI Partition AssistantThe Best Windows Disk Partition Manager and PC Optimizer
Step 1. Install and launch AOMEI Partition Assistant. Right-click the drive to which you want to assign a drive letter, select “Advanced” and then “Change Drive Letter”.
Step 2. Select the released drive letter in the pop-up window.
Step 3. Click “Apply” to view pending operation and then “Proceed” to commit the operation.
AOMEI Partition Assistant is an excellent hard disk and partition management tool. It also offers many more features related to disk partitioning, including:
🔥Partition size adjustment: This tool allows users to adjust partition size without losing data, whether partition size expansion or decrease will meet user storage needs to optimize disk usage. In partition management area, it also offers these powerful functions:
🔥Copying and cloning drive: You can transfer HDD OS to SSD without any data loss and reinstalling on Windows 11,10,8,7.
🔥Drive conversion: Users can easily convert disks like converting from MBR to GPT or converting back without losing data.
🔥Drive performance optimization: AOMEI Partition Assistant also features a hard drive health monitor function that optimizes SSD performance and reduces wear and extends drive life
AOMEI Partition AssistantThe Best Windows Disk Partition Manager and PC Optimizer
Fix 2. Check for external device interference
If your drive letter keeps changing, it may be due to an external device conflicting with existing drive assignments. Windows automatically assigns letters to newly connected storage devices, which can sometimes cause unexpected changes.
To troubleshoot this, try unplugging any unnecessary external drives and then check if the issue is resolved. If the problem stops, you may want to manually assign a permanent drive letter to prevent future conflicts.
Fix 3. Reassign drive letter with Diskpart
Diskpart is a built-in Windows tool that lets you manage disks and partitions directly from the Command Prompt. With Diskpart, you can perform tasks like formatting, creating, or deleting partitions efficiently. If you need to reassign a drive letter using Diskpart to fix drive letter changed by itself issue, please follow these steps:
Step 1. Press "Windows + R". Then, type "diskpart" and press Enter. Type in "list volume" and press Enter. Now, you can see all volumes on PC.
Step 2. Type in "select volume 7" and press Enter(here take volume 7 as an example). Finally, type in“assign letter=F” and press Enter.
If you want to remove the drive letter, type “remove letter=X”(X is the drive letter you want to remove).
Actually, you may assign a drive letter when you create a new one. For that, you need to create partition first. After creating a partition, type “assign letter=?” to that partition. Or, if there is some volume hidden, it will not have the drive letter, to unhide it, you need to assign a drive letter for it.
Conclusion
Drive letter changed by itself can be frustrating, but they are usually caused by simple issues like system updates, external device conflicts, or partition data corruption. Fortunately, there are straightforward solutions to fix the problem, whether it’s through Disk Management, Diskpart, or using third-party tools like AOMEI Partition Assistant. By understanding the common causes and following the steps shared above, you can easily manage and reassign your drive letters to keep your system running smoothly. If the issue persists, consider regularly checking your external devices and using partition management tools to ensure everything remains organized.
AOMEI Partition AssistantThe Best Windows Disk Partition Manager and PC Optimizer
