If you are trying to copy files that are too large and then you received this warning from Windows 11 while transferring big files to an external hard drive or a hard disk.
The file “File Name.rar” or “File Name.*” is too large for the destination file system.
So you questioned yourself, “What on earth could be causing this problem?” My external hard drive has a lot of free space, so why couldn’t I transfer the file?

The most typical reason for this problem is that your file was 4.5 GB in size and that it was saved on an external hard drive/a hard disk with a FAT32 file system. The maximum filesize for FAT32 is 4GB. The maximum filesize for FAT16 is only 2GB!
There are 3 solutions: Move some other data to another drive or partition, divide the big file into smaller pieces and then transfer them or you can convert a FAT file system to NTFS, there are no restrictions on file sizes.
Split huge files into smaller ones using the FFSJ

If you are looking for an easy way to split and join files, this software is for you. FFSJ is a free file splitter and joiner utility that will help you quickly create smaller files from larger ones or combine multiple small files into one big file. It can handle the splitting of large audio/video/image/data archives over 4GB in size on any volume without any data loss!
The features include:
- Split your file into smaller pieces with the click of a button
- Join all your smaller files back together
- Works with large archives greater than 4GB in size
- For added protection, encrypt the output files.
How to use FFSJ to Split Your File
Choose your Source file and Output file location before splitting a big file with FFSJ. Click Split button then.

When you want to combine the files, open FFSJ and go to the Joining tab.

Select the folder containing the first split file part and add an output folder for your restored files.

Click Join and that’s all.
How to Convert FAT32 to NTFS with Windows Terminal (Admin)
The best way to prevent data loss while moving FAT32 to NTFS is to make a backup ahead of time.
You can convert a Windows drive from FAT32 to NTFS with the built-in Windows tool, but this won’t work for the drive containing your Windows installation.
If you want to use the second technique, read my article on How to convert a hard drive from FAT to NTFS without losing data below:
To launch a Windows PowerShell/Windows Terminal (Admin) window, right-click the Start menu buton and choose Windows PowerShell/Windows Terminal (Admin) from the menu.

In a new open window, type the following command: convert G: /fs:ntfs, with G: is a correct drive letter you want to convert.
convert G: /fs:ntfs

It will take some time to complete the process. After the conversion is complete, your hard drive’s file system should have changed to NTFS with no further action required.

If you can’t split the file for whatever reason and don’t want to convert the drive’s file system to NTFS, it’s the only way to improve the situation: try to compress the file or convert it. The Windows 7, Windows 10, and Windows 11 include built-in compression tools, but you may also use third-party applications like 7-Zip, Winrar, Winzip, etc.
Conclusion
The file size is an important factor when deciding to use FAT or NTFS. A file that exceeds 4GB in size cannot be saved on a FAT32 File System, which means you’ll need to convert the File system from FAT32 to NTFS if your external hard drive/hard disk has more than 4 GB of free space available for data storage.
If this doesn’t work and there are no other solutions, try compressing the file with Windows’s built-in compression tool or using third-party tools like Winzip, Winrar, etc. The article also mentions how splitting big files into smaller pieces can help solve some problems by reducing their size before moving them.
We hope these solutions will come in handy as you’re preparing to transfer large files from your hard drive onto other devices.