Bug opening files with overlong paths (259+ characters)

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xyMOREr
Posts: 1
Joined: 08 Nov 2025 01:07

Re: Bug opening files with overlong paths (259+ characters)

Post by xyMOREr »

Preamble: I have resolved this problem, am posting this here in the interest of others. I know this does not follow the thread, but this is the nearest forum topic I can find. Consider this a useful footnote if you will:

Context:
  • XYPlorer 27.20.0200 (32 bit), Support overlong filenames is ticked in the config.
  • OS Name: Microsoft Windows 10 Pro
  • OS Version: 10.0.19045 N/A Build 19045
  • System Type: x64-based PC
Issue:
I ran a Custom Copy using XYplorer of a number of files and at the end XYplorer reported several FAIL messages such as this one:
FAIL (other reasons) New F:\Carson\GoodSync Backup\Users\Carson\WinDevel\JSIL\JSIL.Libraries\node_modules\gulp\node_modules\gulp-util\node_modules\dateformat\node_modules\meow\node_modules\read-pkg-up\node_modules\read-pkg\node_modules\load-json-file\node_modules\parse-json\node_modules\error-ex\index.js -> C:\Users\carson\WinDevel\JSIL\JSIL.Libraries\node_modules\gulp\node_modules\gulp-util\node_modules\dateformat\node_modules\meow\node_modules\read-pkg-up\node_modules\read-pkg\node_modules\load-json-file\node_modules\parse-json\node_modules\error-ex\index.js | The system cannot find the path specified.

Resolution:
After considerable research I discovered that the errors had to do only with the longest pathnames being copied. I further discovered a well-documented problem where the Windows API fails to create pathnames longer than 260 characters (for the record, it's slightly more complicated than that). This is documented by Microsoft here..

I then configured my Windows 10 installation to Enable Win32 Long Paths (by changing the Group Policy setting from Not configured to Enabled as shown in the foregoing MS article).

I then retried the failed copy and the resulting error was identical.

I then exited XYExplorer and restarted it. Now the copy succeeded, copying a folder and all its contents.

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Re: Bug opening files with overlong paths (259+ characters)

Post by admin »

Thanks for the tip!

I wonder if this is maybe a Windows 10 thing? I can Custom Copy overlong paths without problem in Win8.1 and Win11 both being without that LongPathsEnabled=1 bit.

It is (or should be) handled via manifest XYplorer.exe and XYcopy.exe:

Code: Select all

<!-- Support overlong paths on Windows 10 and later. -->
<application xmlns="urn:schemas-microsoft-com:asm.v3">
    <windowsSettings xmlns:ws2="http://schemas.microsoft.com/SMI/2016/WindowsSettings">
        <ws2:longPathAware>true</ws2:longPathAware>
    </windowsSettings>
</application>

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