Why Can't I Copy Large Files to Flash Drive? - Troubleshooting
Flash Drive File Size Limitations Explained
You’ve acquired a new flash drive with substantial storage capacity, potentially exceeding the hard drive space of older computers. However, you encounter an issue when attempting to copy a large file. This article details the reasons behind this problem and provides a solution to resolve your flash drive frustrations.
Understanding the Error Message
A reader contacted us, describing an inability to copy DVD ISO files to a newly purchased 64GB USB 3.0 flash drive. Despite the drive’s ample capacity, the transfer failed with the error message: "The file 'DVDBACKUP1' is too large for the destination file system." This raises the question: why can’t a 4.5GB file be placed on a 64GB drive?
The issue stems from the flash drive’s file system. This is a method of organizing data storage, distinct from the operating system. It governs how data is stored and retrieved on storage media like hard drives and flash drives.
The Role of File Systems
Numerous file systems exist, each with unique features. These features include error checking, journaling, and permission schemes. They are crucial for various applications.
Most flash drives are pre-formatted with the FAT32 file system. While widely supported and compatible with many applications, FAT32 has a significant limitation.
FAT32’s File Size Restriction
FAT32 imposes a maximum file size limit of 4GB (specifically, 4,294,967,295 bytes). This limitation can easily be reached with large video files, DVD/Blu-ray ISOs, and other substantial data sets.
Although FAT32 remains prevalent due to its compatibility, its file size restriction presents a challenge in modern data storage scenarios.
The Solution: Switching to NTFS
To overcome this limitation, you can change the flash drive’s file system to one that supports larger files. We recommend switching to the NTFS file system.
NTFS allows for files ranging from 128GB to 256TB, providing ample space for even the largest files.
How to Format to NTFS
Before formatting, ensure all necessary data is backed up from the flash drive, as formatting will erase all contents.
- Right-click on the flash drive in Windows Explorer.
- Select "Format..." from the context menu.
In the Format window, change the "File system" option from "FAT32" to "NTFS".
Leave the "Allocation unit size" at the default setting of 4096 bytes. Ensure "Quick Format" is checked.
Click "Start" to begin the formatting process.
Verification and Success
After formatting to NTFS, attempt to copy the large file again. The transfer should now complete successfully.
With the flash drive formatted to NTFS, it can now accommodate files exceeding the 4GB limit, enabling you to utilize its full storage capacity.
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