Cannot copy long file names in Windows

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Joined: 28 Feb 2026

PolXh

Is it possible for FreeFileSync to add a feature like Robocopy so to enable copying long file names? I get "ERROR_INVALID_NAME: The filename, directory name, or volume label syntax is incorrect. [CreateFile]
"

What other solutions do you suggest ?

Thanks
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Joined: 11 Jun 2019

xCSxXenon

This can be enabled via Registry or Group Policy manually. Since it's an OS settings/config, I wouldn't say FFS should do modify this automatically but I have installed many other programs that offer it during installation
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Zenju

FFS has been supporting long file paths since forever. There is nothing that needs to be set up, it's the default. Your target drive apparently doesn't allow them.
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xCSxXenon

FFS has been supporting long file paths since forever. There is nothing to that needs to be set up, it's the default. Your target drive apparently doesn't allow them. Zenju, 28 Feb 2026, 20:05
Interesting, I always thought the OS had to have it configured to work at all. I just always have that configured anyway, so I assumed that's why FFS worked fine. Nice to know it works even if the OS isn't configured for it
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Zenju

Interesting, I always thought the OS had to have it configured to work at all. I just always have that configured anyway, so I assumed that's why FFS worked fine. Nice to know it works even if the OS isn't configured for it
Yes, lesser software needs the registry setting :D
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Joined: 28 Feb 2026

PolXh

It worked on an ubuntu-ubuntu connection , but it gives an error between two windows 10 . I know that there is software that can interact with long name files on windows but I thought it might be possible to make it possible on FFS on windows by default. It defeats the purpose to have a program like FFS for an important thing like backups to fail on long file names .

Anyway , very good software. I'd donate if I could. I thought posting here might help everyone else.
Thank you for the reply!
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Joined: 13 Apr 2017

Gianni1962

The error you're receiving on Windows

"ERROR_INVALID_NAME: The filename, directory name, or volume label syntax is incorrect. [CreateFile]"

isn't just caused by an excessively long filename, but rather by a whole host of other possible reasons:

Microsoft Learn: Naming Files, Paths, and Namespaces

The fact that you also work with Linux makes me think you're having trouble with the differences in file and folder naming conventions between the two operating systems:

Google: Filename incompatibility between Windows and Linux
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Joined: 11 Jun 2019

xCSxXenon

It worked on an ubuntu-ubuntu connection , but it gives an error between two windows 10 . I know that there is software that can interact with long name files on windows but I thought it might be possible to make it possible on FFS on windows by default. It defeats the purpose to have a program like FFS for an important thing like backups to fail on long file names .

Anyway , very good software. I'd donate if I could. I thought posting here might help everyone else.
Thank you for the reply! PolXh, 01 Mar 2026, 13:05
As stated by the dev, FFS DOES support long file names, so that is not your issue. The other reply may be worth looking into for further diagnosis. We'd need screenshots or specific paths, names, and error messages to really help