Why flash drive ask to be formatted?
Sometimes, your computer will ask you to format the USB flash drive. That's to say, your flash drive may be corrupted or damaged. And you are not able to open USB stick and the data on it.
Then, I will list the common scenario in the following.
- USB drive holds bad sectors and displays "disk needs to be formatted”.
- USB drive is blank or has an unsupported file system.
- "Please Insert Disk into Removable Disk".
- USB drive shows 0 bytes or "folder is empty”.
- The virus has infected the flash drive and corrupted the files in it.
- "USB Device Not Recognized or Malfunctioned".
- "You need to format the disk before using it".
How to fix a corrupted flash drive without formatting?
When you receive the error message mentioned above, you may worry about two things. The first, how to recover files from a flash drive without formatting? The second, how to fix a corrupted flash drive without losing data?
Don't worry about it. See below and I will help you solve the problems step by step. Taking data loss into consideration, you'd better recover files first and fix damaged drive later.
Recover files from USB using CMD attrib
Step 1. Open CMD. You can press Win + R to summon the Run window, then type cmd.exe and click OK.
Step 2. Check if your drive has bad sectors. In the command prompt, type the following command and hit Enter.
chkdsk E: /f (E is the drive letter of your USB device)
Step 3. Type Y If the drive is in use and hit Enter key to proceed. If the CMD does not prompt, you can see Step 4.
Step 4. Get the deleted files back. You can type the following command and press Enter to run it.
attrib –h –r –s/s /d E: *.*
-h command assigns the Hidden attribute to the selected files.
-r refers to Read-only attribute: files are readable and cannot be changed.
-s assigns System attribute to the selected files.
/s implies to search the specified path including subfolders.
/d command includes process folders.
After all operation finish, you will find all the recovered files saved on your USB drive with a newly created folder. By default, the files will be in .chk format. But you still can change the file format and save it at the preferred location.
If you cannot recover your files, you can try data recovery software. In general, most of the software can scan and recover your files. You can use Recuva. It's free and works fine.
Fix a corrupted USB without formatting it
Test different USB ports on different computers
USB port can be one of the reasons that your flash drive does not work properly. I recommend you to check the USB port.
Assign a drive letterforUSB
Sometimes, the computer cannot assign a drive letter for external USB drive owing some unknown reasons.
Thus, you can plug your drive into the computer and manually assign a drive letter for it.
Step 1. Press Win + R to open the Run windows and type diskmgmt.msc
Step 2. Right-click your drive, select Change Drive Letter and Paths from the context menu.
Step 3. Click Add, select a drive letter in the drop-down menu and hit OK.
Step 4. See if you can open your drive and access your data.
Fix corrupted USB on windows 10/8/7
For Windows 7/8
Step 1. Connect USB drive to PC.
Step 2. Open Computer or This PC, right-click Removable Disk and open its Properties.
Step 3. Click on Tools, tick the Check Now option and check Automatically fix file system errors and Scan for and attempt recovery of bad sectors.
Step 4. Click Start to begin the scan process. Wait and click Close once the process complete.
For Windows 10
Step 1. Follow Step 1 and Step 2 for Windows 7/8
Step 2. Click on Tools, tick the Check option and tick Automatically fix file system errors and Scan for and attempt recovery of bad sectors.
Step 3. Wait and click Close once the process complete.
Step 4. Right-click the USB drive icon and select Eject to remove from the existing port.
A little advice
What if you format USB flash drive?
When you are asked to format your USB drive, you can format it or not. In general, I will recommend you not to format it before you recover the files. But, there are some people who may accidentally format it.
Don't panic. Even if you format the USB thumb drive, you still can restore your data. Because every file has its structure, including directory and blocks. When you format the drive, you just remove the directory of it. All your files are marked as unimportant and keep intact here.
You need to pay attention to the following things.
1. Stop using the USB drive.
2. Do not add new items to USB stick.
3. Do not reformat the USB flash drive.
No matter what storage device you use, there is a risk of data loss. When your storage device runs into problems, you can recover it via various ways. But you are not sure you can recover all your files.
Thus, I think you need to create an exact copy of your files in advance. The simplest way is to backup files using backup and restore software like AOMEI Backupper.
With it, you can backup large files, backup files with certain file extension, only backup the changed files, backup specific folders, etc. And all the steps are very easy. You just need to download this software and launch it, then follow the prompts in the wizard.
During the process, you can enjoy more advanced features. You can compress your backup if you have dozens of files. You can backup files at a regular interval, including daily, weekly, monthly.
Also, if you want to backup files at a specific point, you can choose event-trigger backup. It contains four types. You can choose to backup files at System shutdown, System Startup, User logon, User logoff.