Sometimes, a USB drive used in Ubuntu may become unusable after being inserted into a Windows system, displaying a message that it needs to be formatted. This issue can occur due to several reasons:
1.File System Metadata Corruption: Windows might modify the file system metadata if it detects inconsistencies, causing Ubuntu to be unable to recognize the drive.
2.Improper Unmounting: If the USB drive is not properly unmounted in Windows, it may not update the file system state correctly, leading to issues when it’s reinserted into Ubuntu.
3.File System Compatibility: Different operating systems manage file systems differently. Switching between Windows and Ubuntu can sometimes cause compatibility issues, especially with exFAT or NTFS file systems.
If your USB drive shows as unformatted in Ubuntu after being used in Windows, you can use PhotoRec to recover the data.
1. Installation.
sudo apt-get install testdisk
sudo photorec2. In the PhotoRec interface, select your USB drive (e.g., /dev/sda) and press Enter.
3. Use the arrow keys to select the P exFAT partition and press Enter.
4. Select [ Whole ] to scan the entire partition and press Enter.
5. Select a target directory to save the recovered files, ensuring there is enough space available.
6. Confirm all options and press Enter to start the data recovery process.
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