Thank you for the bug report.
This particular file runs into three different issues:
- The file has too many layers to load into Paint.NET. Because Photoshop has partial layers and Paint.NET doesn't, files with lots of layers will blow up enormously in memory consumption when loaded into Paint.NET. This particular file has 1279 layers, with pixel dimensions of 6200 x 3716. At 4 bytes per pixel, it would require 118 GB of RAM to load into Paint.NET.
- Layer index 472 contains both a user mask and a vector mask. The PSD plugin does not properly handle this situation. This is what's causing the "erreur non spécifiée."
- The file has malformed layer groups. The webpage hosting the file states that it was created in Photoshop CS6 beta -- which probably explains the bug. I'm still using CS4, which produces a warning message: "Some groups were found corrupted and repaired."
I can fix problem 2 and ignore the error in problem 3, but you still won't be able to load the file unless you have more than 118 GB of RAM.
Unfortunately, this doesn't help you directly. However, once I fix 2 and 3, at least they won't prevent other people from loading similar files -- that is, files with fewer layers.