Same issue with sample SpineBoy:

I'm not sure why this D:/a directory is referenced since my Godot binaries reside on C disk. Moving Godot .exe from C disk to some other drive didn't help either in case this is some very weird permissions issue.

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Fixed it by disabling the pre-multiply alpha checkbox. Still not working unfortunately.

It seems to be working even with the import error popping up. I can create the SkeletonData resource and assign the .skel and atlas. What confused me was that the imported files don't have the Spine icon like in the official documentation so I thought none of it is working together with the import error:

Yeah, I see this error message as well and I have no idea where it is coming from. I also have no idea why our icon doesn't show up in Godot 4.x. We supposedly do what the module documentation tells us to do (and it works for 3.x)

I've opened an issue here:
EsotericSoftware/spine-runtimes2385

    I have the same problem, i need help please!

      umbekannt Ignore the error for now, everything works both in the editor and in the build. Create SkeletonData Resource, then assign .skel or .spine-json and atlas to it. Add a SpineSprite node to scene and assign the newly created resource to it. The skeleton will show up and work as intended.

      Hopefully, this can be resolved soon.

        Godot 4.1 doesn't recognize any skeleton format, neither .spine-json nor .skel

          umbekannt You have .json instead of .spine-json. http://esotericsoftware.com/spine-godot#Exporting-for-Godot

          Note: You should prefer binary skeleton exports over JSON exports, as they are smaller in size and faster to load. If you must use JSON, make sure the file extension is .spine-json instead of .json. If you have an existing project that still uses .json export files, you can use this Python script to convert it to the new .spine-json extension.

          Image removed due to the lack of support for HTTPS. | Show Anyway

          And try one format at a time, delete contents in Godot, then reexport with correct file extension.

            I have the same problem with the .spine-json format 🙁

              umbekannt uff, then I dunno. Try resetting Spine export Pack Settings to Default. There's a button for it, then disable the Premultiply alpha checkbox. There's a note in docs that premultiply alpha is not supported. That's my last guess.

                It still doesn't work, but thank you very much for your time; you're a great person!

                  8 days later

                  umbekannt Hey, if you're still around, can you share your OS and hardware specs in the very unlikely case that they are a contributing factor?

                  Here're mine:
                  Spine 4.1.23
                  OS: Windows 11 Home version 22H2
                  CPU: slightly downvolted i9-12900k
                  RAM: 32Gb DDR4
                  Drive/s where Godot/Spine reside: Samsung 980 PRO PCle 4.0 NVMe M.2
                  GPU: RTX 3070Ti /w latest Nvidia gaming drivers

                    10 days later

                    I am using Godot 4.1.2 with C# support
                    When exporting as binary I still cannot seem to use the .skel file in Godot editor.

                      Lick I tried to reproduce the problem but unfortunately was not able to see the error. Are you encountering this problem on Windows or Mac?

                      • Lick replied to this.

                          Misaki
                          Hello Thanks for the response!
                          I am on Windows 10. I think it may have to do with my Spine version...
                          What is the minimum Spine version that is compatible with the Godot runtime?

                              Lick spine-godot works with data exported from Spine 4.1.xx, so it cannot be imported if your data was exported with a version prior to 4.1. For your information, the data I tried was exported from Spine 4.1.23 (and I did not get the error).

                                  I've been having a similar problem and was trying to diagnosis it using this thread: https://esotericsoftware.com/forum/d/24751-spine-godot-c-support/19 only to realize it wasn't addressing this problem but just that stuff wouldn't work after importing in general, here the example projects seem to run fine despite this error so maybe it's ignorable for now? Running windows 10 with spine version 4.1.23, with premultiply alpha disabled on exporting, tried running godot on different drives too.

                                  10 days later

                                  The weird directory path is probably from the build machine.

                                  I do want to use Godot, but I'm reluctant while this issue persists. If importing already is so error prone, I shudder to think what might happen 6-12 months in production.