Sometimes, when I copy my stuff to an external drive, some files are not copied.
A message says that it cannot be copied because they have a long file name. I
don’t understand why this should be a problem and anyway, what can I do since
I need to copy those files too? Often it’s hard to specify their locality and
if they are many, forget about it! Windows 7, 64, but in previous versions, I’ve
had the same problem.
In this excerpt from
Answercast #69, I look at possible reasons a drive would not be accepting
files with long file names.
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Files with long names
The problem is the format used on the external drive.
Realize that Windows (and DOS before it) began supporting only file
names with eight characters – followed by an up to three-character extension after
the dot. That’s why so many of the operating system files are eight
characters-dot-three because of simply legacy. That’s the only way things
Now, at one point, they added long file name support to the operating system.
That required that the disk format actually be changed to be able to
handle long file names – where file names could be up to something like 255
characters long with an arbitrary amount of periods, the extension could be
any length, and so forth.
Disk drive format
The problem is then that if you have one of these hard drives or one of
these external drives that is using a disk format that does not
support long file names – well, you can’t copy files that have long file names
to that drive.
So, what I would recommend you do is:
Double-check the format of the external drive that this happens to;
And if appropriate (in other words, if all the systems that it might be
connected to can support it), convert that drive to NTFS.
Converting from FAT to NTFS
Most versions of FAT will handle long file names. Older versions of FAT do
not – and quite honestly, I’m kind of surprised that you’re running into
NTFS, by definition, will handle long file names. It’s a simple “convert
command” to actually convert the external drive from one file system format to
I have an article on how to convert that. It’s a command you run in a
Windows Command shell. The net result is that you will have a disk that uses
NTFS instead of the FAT file system and then it can use or support long file
Long file paths
The only other thing I can think of that might cause you to run into this
problem is if indeed your file names are multiple hundreds of characters long
– or if the combination of the file folders and the file name exceeds something
like 256 or 512 characters long.
In other words, the entire path to a file has a limit on it as
So, I recommend you certainly look at those scenarios when it’s reporting the
error. But if it’s happening regularly, if it’s happening on one specific
device, the first thing that I would confirm is that the file system on the
device you’re copying to can in fact handle long file names.