Interesting.  I do wonder what's going on with this, then.

Do current versions of Poser still do this?  If so, perhaps the Poser team should be advised that the library system should ignore shortcuts.

That fixed it, all right.  Thank you, Richard60.  That was driving me bonkers.

So what creates a shortcut, and why would it do that?  Huh.

Was the library trying to follow the shortcut, or treat it like a folder, itself?

No luck.  I renamed the file, then tested opening Poser.  The same error resulted.  I deleted the new file and also renamed the other two library files in Poser's AppData folder, but still the same error message.

Then I tried opening numerous files in Poser, using the double-click approach, assuming that Windows was keeping a list of most-recently used files somewhere, and I might be able to fill up that list with new entries.  That did not help, and the error was thrown every time one of the files was opened.

Then I searched the registry, using Regedit, for Libraries/Pose.  All I found were two listings belonging to Poser File Editor.

Then I searched for all files modified during the period that this has been happening, and starting a few days before the error.  There were no files listed that were unrecognizable, no data files of any kind that might store a path like this.

Somehow, somewhere, either Poser or Windows must be keeping some kind of record of opened files, to be able to throw this error.  I have no idea where that might be.  My next test will involve replacing standard Poser installation files from backup, but I don't expect that to help.  That old library involves complications with Flash and (Tarim help us all) Internet Explorer, so who the heck knows what could be happening out there.

I know what I was doing, when the error began.  I was using a Python script to generate poses.  It was an older script that turned out to have some errors -- Poser files can apparently have more varied bracket formatting than we had assumed while developing it -- so I was modifying the script as I went along, as well as creating and deleting and recreating poses the whole time.

I don't think I deleted any folders.  I did create a few during the process.  The transitional files, all those WIP poses, are long gone.

IIRC, in the midst of all of the above, I was working in that pose folder, possibly examining the files in Poser Editor, when I double-clicked one and oops.

Interesting.  I did not try to rename it, but I did study that file.  I don't think I modified it; IIRC, nothing in it seemed obviously linked to the problem.  But I do not really know what the problem may be, okay so.

I will try these suggestions.  Thank you.

Sadly, the above did not work.

Possibly I should have noted at the outset that the message appears as the library is being loaded.  Poser 10 had the old Flash-based library, if that means anything.

Ah, so it's not the folder's permissions, but Poser's?  That did not occur to me.  I will give that a shot.  Thank you.

Oop.  I didn't refresh the page like a should've.  I realized my mistake, BB.  Thank you.  This has helped a lot.  I did not know that addons could bedevil me across Poser versions, but now I do.  Dang.

I have Python/addons/PythonShell, with poseraddon.py also in addons.  I also have a copy of EZMat, in addons.  That was a Snarly project, IIRC.  I'm going to zip up that folder and delete the original.  Now, some savetests.

[EDIT]

I see, you wanted me to check the pulldown menus. I did have Subdivider showing up in the menu! I dug through the folders and there was a copy of Subdivider in the PoserPro2012 installation. Why did I not find it yesterday? Bits are falling out all over the place. Dang.

Removing the 2012 addon cleared the 2014 problem. So apparently addons are loaded across versions, when the runtimes are linked. It's a helluva thing.

This has driven me nuts, and hopefully now it is fixed. Thank you, folks, for tolerating my bumbleheadedness.

That's the assumption I've had, BB, yes.  It has had me deleting the line from all my pz3 files, including my default scenes.  I made a fresh round of such edits a day or two ago, yet the line mysteriously returned, which prompted this thread.

My process has involved deleting the line from any pz3 I am likely to use, then saving the changes.  Then, when using Poser, if I open any uncorrected scene I close and reopen Poser afterwards, to avoid contaminating the cleaned files.

Did they offer an off switch for this feature?  On account of I could use one, oh boy.

I wanted to note here that I have gotten useful results with the Firefly methods revealed upthread.  The images I posted above showed a problem when shadows were used on the two-sided cloth in a scene with IBL lighting.  As illustrated in the images I posted (although not explained properly at the time), the two-sided effect is broken wherever a shadow is cast upon the two-sided item.  The fix is to set all shadow-casting lights' shadow intensity below 1.0.  At shadow strength 0.95, the effect works as desired, but at strength 1.0 the whole thing fails as I've noted.

I have not tested anything with IDL and would guess that it would fail, as smarter users than I have already noted, up there in 2022.

Interesting.  The documentation would seem to suggest that my problem is actually that this absent addon that is not installed is still somehow running every time I open Poser and is saving its preferences on a per-scene basis, when I save.  I do feel justified in kvetching that addons seem like they may not have been implemented as robustly as they might have been.  But Sunfire is correct, in that I have been doing things sideways and backwards and not meeting the programmers' expectations for maintaining a clean installation.

All of this give me some hints about how to dig around for this.  Thank you, all.

Ah, I missed Rhia.  I don't think a ticket would help anything, as no one is going to update Poser Pro 2014.  I no longer fit the parameters for using newer versions of Poser.

Ah.  I haven't installed a new version of Poser since I was a beta tester, at the tail end of the Smith Micro era.  I have installed Poser Pro 2014 onto the newer device, but I do that with a fresh install, mainly to set things up in the registry, after which I overwrite everything by copying over my preexisting installation and runtimes.  I am still on Windows 7, as well, with a device no longer allowed to touch the internet.