Long File names failing to import with Lightroom Classic

[Phil5C29]

Re: Importing long file names

It appears that LRC will fail to recognise a valid file (TIFF,RAW etc) if the file name including the path exceeds 255 chars. So when you try to import I just get "No Photos Found". My file name + path was actually 288 chars including spaces and backslashes

If I reduced the char count to 255 using the same TIFF file it works fine.

Anybody else had this problem?

I am using the latest Lightroom Classic version 12.4 Release running under latest Windows 10 update

[dj_paige]

Lightroom Classic, and really all programs, cannot override the limits set by Windows for length of path+filename

[FSt0p]

Actually, it can.

https://learn.microsoft.com/en-us/windows/win32/fileio/naming-a-file

In editions of Windows before Windows 10 version 1607, the maximum length for a path is MAX_PATH, which is defined as 260 characters. In later versions of Windows, changing a registry key or using the Group Policy tool is required to remove the limit.

For file I/O, the "\\?\" prefix to a path string tells the Windows APIs to disable all string parsing and to send the string that follows it straight to the file system. For example, if the file system supports large paths and file names, you can exceed the MAX_PATH limits that are otherwise enforced by the Windows APIs.

https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfilea

The name of the file or device to be created or opened. You may use either forward slashes (/) or backslashes (\) in this name.

By default, the name is limited to MAX_PATH characters. To extend this limit to 32,767 wide characters, prepend "\\?\" to the path.

It just also requires support from the application.

It's not implemented not because it's impossible, but because noone cares.

[Phil5C29]

Thanks for that. I spent ages trying to work out why LR was failing to see a valid image. A more helpful error message would have been useful such as "Cannot import - Filename+Path exceeds Windows 255 limit"  It was just a guess that might be the problem.

[dj_paige]

Please suggest an improvement to Adobe.

[Phil5C29]

Will do. Actually you can set Windows 10 to accept long file names by several methods such as Registry or Group policy edits. But that does not mean applications such as LR have to allow it. The odd thing is that the file opens perfectly ok in PS.

[FSt0p]

This will only enable long paths in the system, but also requires support from the application.

To change it's manifest and also change internal path limit.

You can read here: https://learn.microsoft.com/en-us/windows/win32/fileio/maximum-file-path-limitation?tabs=registry

Registry or GP edit is only first step of the two required.
And second step can only be done by application developer.
You can edit manifest, but this will not help as path limit is build into application binary.

[Phil5C29]

Thanks for the info. I think I will tidy some of my folder structure to reduce file and path names which were getting ridiculously long anyway, That way I can concentrate on my photography not windows development where I would be way out of my depth. Stack exchange and other forums have a lot of in depth discussions on this subject. Adobe have not been consistent across their product range