Modern file systems on both Mac and Windows mean that it’s rare to encounter errors when you’re copying files between one operating system and the other. However, many of us still use old hard drives and USB sticks to transfer files, and that’s where issues can crop up. One of those issues results in the error message explaining that ‘the item can’t be copied because it is too large for the volume’s format.’ But what does that error mean, and what can you do about it? We’ll explain all that in this article.
What does ‘can’t be copied because it is too large for the volume’s format’ mean?
If you’ve seen the error message ‘can’t be copied because it is too large for the volume’s format,’ you may have been confused because it seems like it’s telling you that the file is too large for the disk you’re trying to copy it to. But that’s not what the error means. Look closely at what it says. It’s telling you the file is too large for the volume’s format, not for the volume itself.
What does that mean? It means that there is enough space on the disk for the file, but the way it is formatted is preventing the file from being copied. And the reason for that is almost certainly because it’s formatted as FAT-32. FAT-32 has a maximum partition size of 32GB and, more importantly for us, a maximum file size of 4GB. So, if the file you’re trying to copy is larger than 4GB, it won’t copy. Given that lots of high-definition and 4K video files, as well as many installers, are larger than 4GB, that’s a problem that’s going to crop up fairly often.
How to fix ‘can’t be copied because it is too large for the volume’s format’
The solution to the problem is to reformat the disk. FAT-32 is a widely compatible format and was very useful if you needed to copy files between a Mac and a PC. However, it’s a legacy format, and its limitations mean that it’s much less useful than it used to be. So, it’s much better to reformat the disk using a modern file system. If you only need to use the disk with Macs, you should choose APFS. Otherwise, exFAT is a good alternative to FAT-32. It supports file sizes and partition sizes that are several orders of magnitude higher than FAT-32.
Before reformatting your disk
If you decide to reformat your disk, you may want to back up files you store there, just in case you need them later. Before reformatting your disk, make sure that you do not back up junk files and remove any unnecessary large files. The easiest way to do it is to use a third-party tool.
We recommend CleanMyMac X — it has a menu bar item that allows you to check the available space on an external disk and clear junk files from it. CleanMyMac X is free to download here. Once you’ve downloaded and installed it, follow the steps below to clear out junk files on your external disk and delete large files:
- Click the CleanMyMac X menu bar item. If you don’t see it, open CleanMyMac X, click the CleanMyMac X menu, and choose Settings > Menu > Enable menu.
- Choose Connected Devices. Hover over Junk and click Clean Up.
- Then, click Organize next to your external disk. You’ll be taken to CleanMyMac X’s Space Lens tool, where you can select a folder to delete it or dig down into subfolders using the bubble view on the right
How to reformat a disk using Disk Utility
As we said, the solution to ‘can’t be copied because it is too large for the volume’s format’ is to reformat the disk. Reformatting wipes all the data on the disk, so you should back it up first or at least copy all the files you need from it to another disk. Once you’ve done that, follow the steps below to reformat it:
- Go to Applications > Utilities and open Disk Utility.
- Select your external disk in the sidebar.
- Click Erase in the toolbar.
- Choose a format from the Format menu. Choose exFAT if you want to use the drive with a Windows PC.
- Leave partition map as GUID Partition Map.
- Click Erase.
Bonus tip: How to remove large and old files
One quick and easy way to clear space on any disk is to identify and remove those files that are taking up the most space. After all, it’s much easier to free up 10GB by moving five files than it is by moving 50 or more. Also, if you can identify the files that you open least often, you can move those, knowing that it will cause very little disruption to your daily work.
One easy way to identify both these types of files is to use the Large & Old Files module in CleanMyMac X. It scans your Mac looking for exactly those files, then presents them to you in order of size or age, depending on how you want to view them. You can then choose which ones to delete after you’ve moved them to a different disk. Here’s how to use this smart tool:
- Open CleanMyMac X.
- From the sidebar, go to Large & Old Files.
- Click Scan.
- Now, review what the app has found, choose the Removal type, and click Remove.
If you see the error message ‘can’t be copied because it is too large for the volume’s format,’ it means that the file you’re trying to copy to an external disk can’t be copied because the format of the disk — probably FAT-32 — doesn’t allow files of that size to be copied. FAT-32 has a file size limit of 4GB. So, if your file is larger than that, that’s likely to be the problem. The solution is to reformat the disk in a format that supports larger file sizes after copying off any files you need.
