Windows 10: File share Maximum Path Length Limitation

Dear Expert, Our company has some issue that the share drive's path more than 256 characters. https://docs.microsoft.com/en-us/windows/win32/fileio/maximum-file-path-limitation?tabs=cmd as I check, it can extend the limitation on that, but I'm confused if I need to enable it on the file server and local windows 10 at the same time? or just need to enable it on the file server? I'm also thinking about any potential risk/issue for enabling this long path function. Kindly provide your idea in advance.

:)

 

Path length limit

I want to install Python. Should I disable the path length limit? Are there any negatives to doing so?

 

Path length limit

Hello John,

My name is Patricia and I am an Independent Advisor. I am here to help you today.

Disable the path limit length is recommended after Python setup is successful, because if python was installed in a directory with a path length greater than 260 characters, adding it to the path could fail.

So don't worry about that action and proceed to it.

 

Lesser-known effect of path-length limitation in File Explorer in Windows 10

Occasionally users encounter an error when dealing with files saved in deep directory structures, due to a limit on the maximum length of a path (including filename) in File Explorer, which is effectively 259 characters (excluding a required

null terminator). I have seen the effects of this before when using either
SyncToy or xcopy (I forget now which; maybe both).

It turns out that there are a couple of behaviours in Windows Explorer, under Windows 10 (with default settings;
i.e. without a
registry edit to remove the limit).

(1)

Normally it is possible to
copy the path (including filename) of a file from Windows Explorer by either choosing "Copy as path" from the context menu or through Home > Copy path.

It turns out that if the length exceeds 260 characters (259 regular characters plus the obligatory <NUL> character), then Windows Explorer automatically copies the path in "short
filename" format (a.k.a. "8.3 format" / "short name format").

Thus the path of

c:\long\path_name\....\no_really\very_long_path_name\the.long_file_name_01234567890123456789_foo.txt

might get copied to the clipboard as

c:\long\path_n~1\....\no_rea~2\very_l~1\thelon~4.txt

["...." just represents more of the path.]

(2)

Note that I can successfully copy files with longish names to folders with longish names to create paths that exceed the 260-character limit within File Explorer (even with the default settings)*. I can then open, copy and delete those files.

However, if I try to make a copy of the file in the same directory by dragging and dropping with the mouse, while Ctrl is depressed — so that
File Explorer would want to append the suffix " - Copy" to the end (before the extension) — then the name gets
truncated. Not to the 8.3 format, but enough to easily satisfy the path limit.

What do I mean by "easily satisfy"? What I found is that the new filename will be precisely 10 characters shorter than the maximum allowed (taking into account the entire path).

Thus

c:\long\path_name\....\no_really\very_long_path_name\the.long_file_name_01234567890123456789_foo.txt

might get duplicated as

c:\long\path_name\....\no_really\very_long_path_name\the.long_fil - Copy.txt

and manually editing this filename would allow it to be expanded as far as (e.g.)

c:\long\path_name\....\no_really\very_long_path_name\the.long_fil - Copy0123456789.txt

c:\long\path_name\....\no_really\very_long_path_name\0123456789the.long_fil - Copy.txt

I didn't find either of these behaviours documented anywhere else.

—DIV

System information:

OS Name Microsoft Windows 10 Pro for Workstations

Version 10.0.16299 Build 16299

System Type x64-based PC

* This functionality would implicitly be using an
extended-length path, with a limitation of 32767 characters in total (with each constituent director or file's name being no more than ~255 characters).