It can be frustrating when you plug in a USB flash drive and see that it is using space, but you can’t find the files taking up that space. There are several potential reasons why this might happen.
Corrupted File System
One of the most common reasons a USB drive will show used space without files is because the file system has become corrupted. The file system is essentially the index of where all the files and folders are located on the drive. If this gets corrupted or damaged, the operating system may not be able to properly read what files are actually stored.
Some signs of a corrupted file system include:
- Errors when trying to open or copy files on the USB drive
- Files and folders appear empty even though space is used
- Strange file names like “DEX561.tmp” appearing
- Drives asking to be formatted when plugged in
A corrupted file system can happen if the USB drive was not safely ejected before being unplugged, if it encountered errors during file transfers, from physical damage, or general wear and tear over time.
Accidental Format
Another possibility is that the USB drive was accidentally formatted, erasing the file system. This could happen if it was reformatted to a different file system type, like exFAT or FAT32, or if a full format was done erasing all data.
When a drive is formatted, the actual files themselves are not initially overwritten. The space they occupy is just marked as available. Until new data physically overwrites the old files, recovery software can scan the drive and restore the previous files.
So if your USB drive was formatted recently, the old data may still be present but just no longer accessible through normal means. You can use data recovery software to scan and restore the original files.
Hidden Files and Folders
Drives can also show full space used without visible files if there are hidden files or folders present. On Windows, files and folders marked as hidden do not show up in normal directory listings.
Some ways hidden files can end up on a USB drive include:
- System files like thumbs.db or desktop.ini files that store thumbnail previews or folder settings
- Virus or malware infections that hide files
- Sensitive files a user has intentionally hidden
- Backup folder structures with system files marked hidden
You can make hidden files visible in Windows by going to Folder Options and selecting “Show hidden files and folders”. This will expose any system files or intentionally hidden data.
Partition Issues
Problems with the drive’s partition table can also lead to used space not matching visible files. The partition table tells the operating system how the drive’s storage is logically divided up.
If this gets corrupted, the OS will see the full capacity of the disk but will not be able to properly access all of the partitions and data they hold. This can happen if Partition Manager programs encounter errors, or if the physical media has defects.
You may see only a small primary partition with files, while a larger secondary partition is marked as raw unused space. Trying to view this unused space results in errors. Specialized partition recovery software can rebuild the damaged partition table in many cases.
Failed Drive Recovery
In some instances, the mismatch between used space and visible files is caused by failed attempts to recover data from a damaged drive using software tools. Recovery software can sometimes create disk images or snapshot data on the drive as part of attempting repairs.
If the software encountered errors or did not finish properly, leftover data fragments can accumulate on the drive and appear as used space. But these fragments may not be complete valid files you can access normally.
Attempting recovery again or restoring from backups may overwrite the remnants and resolve this discrepancy in usage.
Shortcuts Pointing to Removed Files
On Windows USB drives, another possible cause for space issues are shortcuts pointing to files that no longer exist. When you delete the original file a shortcut pointed to but leave the shortcut, it will still take up space.
To check for invalid shortcuts, examine the drive properties to see usage, then go through each folder manually checking sizes to see if they add up. Any discrepancy may be caused by shortcuts. You can then selectively delete shortcuts and see if usage changes.
How to Fix USB Drive Space Issues
Based on the potential reasons outlined above, here are some steps to try fixing a USB drive showing full space but no files:
- Scan for and remove any malware – Some viruses can hide files and manipulate space.
- Unhide hidden files – Make sure there are no system or intentionally hidden files.
- Check shortcut file sizes – Delete any invalid shortcuts to nonexistent files.
- Try drive recovery software – This can rebuild corrupted file tables.
- Format the USB drive – This will completely erase and recreate the file system.
If drive formatting does not fix the issue, the USB flash drive is likely physically damaged and may need to be replaced.
Preventing USB File and Space Issues
You can help avoid many of these USB drive problems by following proper storage practices:
- Always safely eject the drive before unplugging it
- Don’t unplug flash drives while files are still transferring
- Keep backups of important USB drive data
- Store and carry drives carefully to prevent physical damage
- Scan drives occasionally for errors using CHKDSK
Following these tips will help maintain the integrity of the USB drive’s file system and ensure your important data remains accessible.
Recovering Files from Problem USB Drives
If you are having USB drive space issues as described, all hope is not lost for recovering your files. Even if they are not visible normally, advanced data recovery software can often help retrieve your important documents, photos, and other files.
Data recovery specialists have access to forensic tools that can read even technically damaged media at very low levels to reconstruct file tables and pull data. This is done in a read-only mode to avoid overwriting anything.
Some options for professional USB drive file recovery include:
- Remote recovery services – You ship your USB drive to a lab, they recover the data in a clean room environment, and send you a new external hard drive or cloud download link with the recovered files.
- Local recovery specialists – Major cities have data recovery companies with clean rooms who can attempt repairs and retrieve files directly.
- Computer repair shops – Some independent computer technicians have data recovery capabilities on-site and can assist with USB drives.
The chances of successful data recovery depend on the physical condition of the drive and nature of the file system damage. But reputable recovery firms can often reclaim 50-100% of files as long as the USB flash memory chips are intact.
So don’t give up even if your external drive seems to have used space but no accessible files. With the right tools it is possible in many cases to get back your precious photos, documents and other personal or work data.
Conclusion
A USB flash drive showing full space usage but not displaying files can be caused by many recoverable issues like:
- Corrupted file system
- Accidental formatting
- Hidden files
- Partition problems
- Failed drive recovery attempts
- Invalid shortcuts
By analyzing drive errors, scanning for malware, unhiding system files, and using file recovery software, it is often possible to restore missing data on these problematic USB drives. This allows you to regain access to important documents, photos, videos, and other personal files.
Following proper USB storage practices can also help prevent file system damage or data loss on external drives going forward.