1.10.1 Cannot open UNC paths if longer than 255 characters

[ugo92]

XnView: MP 1.10.1 - 64 bit
OS: Windows - 64bit

It looks like the application cannot handle UNC paths longer than 255 characters

Effect: When you try to open files whose path is an UNC path and it's longer than 255 characters, XnView shows an Error dialog with "File not found!" written inside. Shorter file paths are handled just fine.
The difference between a shorter than 255 characters path and a longer than 255 charaters file paths is in the beginning of the path.
The longer one will start with \\?\UNC\server.domain.whatever while the shorter one starts with \\server.domain.whatever


To reproduce:
1. Try to open an image file whose file path is UNC and longer than 255 characters

Actual behaviour (bug): The application cannot find the file

Expected behaviour: The application open the chosen file

[jkm]

Welcome to the forums...

Please read up on MAX_PATH, a historical limitation in Windows.

https://learn.microsoft.com/en-us/windo ... s=registry

To exceed it, you must explicitly enable LongPaths on your machine, individual applications must opt-in to it, and still not all Windows functions support it.

Have you enabled LongPaths?

Hopefully this sheds some light on what's going on.

[xnview]

you enter in the pathname filed, a path like \\?\UNC\server.domain.whatever, right?

[ugo92]

Thanks for your answers!

Have you enabled LongPaths?

Yes, LongPaths is enabled

you enter in the pathname filed, a path like \\?\UNC\server.domain.whatever, right?

No, i use windows file explorer to reach \\server.domain.whatever\level1\level2\...\levelN\ then i double click image.jpg to open it in XnViewMP.
If i go "deep enough" in the levels the file path becomes longer than 255 characters and the image doesn't open.
I checked its path with right click -> copy as path, that's where I noticed the differences in the beginning of the path

[xnview]

No, i use windows file explorer to reach \\server.domain.whatever\level1\level2\...\levelN\ then i double click image.jpg to open it in XnViewMP.
If i go "deep enough" in the levels the file path becomes longer than 255 characters and the image doesn't open.
I checked its path with right click -> copy as path, that's where I noticed the differences in the beginning of the path

i've sent you a test version

[ugo92]

I'm very sorry, I just noticed this answer and the private message.
The link expired, if you can send it again I'm more than happy to test it

Thanks!

[xnview]

please check 1.10.5

[ugo92]

Just tried it, I've got the same "File not found!" pop up.
The path is 283 characters long, and it's starting with \\?\UNC\

Just to add some more information, if I open the same file from the same location with the "Photos" or "Paint 3D" app from Windows 11, it opens just fine

Thanks!

[xnview]

Just tried it, I've got the same "File not found!" pop up.
The path is 283 characters long, and it's starting with \\?\UNC\

i send you a PM

[ugo92]

Thanks, I haven't received it yet

[xnview]

Thanks, I haven't received it yet

sent

[xnview]

Thanks to your detailed description I can reproduce the problem.

[xnview]

This problem is supposed to be fixed in XnView MP 1.11.1. Please check and confirm the bug fix here.