"An internal error has occurred" - attempt to index a field with nil value. A fix/workaround?

[Jay_Warner]

I am running LR 7.4 (Classic CC), with macOS 10.13.6, & everything "stock."  While cleaning up & organizing a sizable collection, some photo files became "lost" & some declined to blank grey with no detail info.  Then I get the internal error msg:

If I isolate a few files to be erased, I can do that, but one/some lead to the error msg & I've no idea which ones.  How can I remove the offenders & get back to smooth working?

[Sahil.Chawla]

Hi Jay,              

We're sorry to hear about this, do you have any third party plugins installed?

Please try the steps mentioned here and let us know if it helps:

Disable the plugins by going to File > Plugin manager.

Regards,
Sahil

[Jay_Warner]

Thank you all for your prompt response. I shall study it closely.

To answer your questions,

1) No I am not using any plugins - this was a stock installation.

2) When I take the time to locate missing folders, the problem occurs less frequently. I have also been deleting smaller groups of files at one time (50 - 200 at once, instead of 500 - 1500). The extra work is worth the added comfort in watching everything behave as desired/planned.

[JohanElzenga]

Please have a look here: an internal error occurred: ?:0: attempt to index a nil value

[Jay_Warner · Accepted solution]

Solution!    Well maybe for me at least.

I think I figured it out.  the catalog was holding 2 records (thumbnails, file info) for a single image file.  When I deleted _only one_ of them, the delete command worked, & both references went away. 

When I tried to delete both records, the dreaded internal error msg came up & it stopped doing anything.

Background:  I am running a 'stock' Mac Pro (late 2013), Mac OS 10.13.6.  With LightRoom Classic CC 7.4, with Camera Raw 10.4, again as installed.  No additional plug-ins.

I am collecting & coagulating over 100,000 images from multiple sources -- old catalogs, old image file collections.  Mostly RAW, with many jpg & a few tiff's.

A number of catalog references turned up missing.  Some to the point of having little or no catalog file information.  At first, I thought these 'file missing' images were causing the 'nil reference' error.  (they may still do that.)

So I went through & tried to locate all the missing files.  This seemed to help.

But THEN I found that some sound catalog image records still woudn't delete or remove.  Some image records appeared twice in a single subfolder.  How could this be?  I could make the machine find them, but then it would refuse to let me delete (or remove) them - nil error again.  when I tried, it also turned them into lost images as well.

then I got bright, or lucky.  When I deleted a single one of these 'doubles', both went away.  So I went through the whole stack, deleting every second reference to the offending images.  (It happens that I didn't want them in any case, so deletion was called for.). This cleared things up considerable, and I haven't seen the nil error msg since then.

One not-so-minor issue:   If I removed one of the doubles, both disappeared.  If I really want the image file in the catalog, I have to add or import it back in.

OK, LR gurus, can you figure out what _really_ happened inside, get the right terms on it, and help us all stay away from those 'nil errors'?  They aren't 'nil' when you hit one.

[Sean McCormack]

Not sure if it's related, but there was a bug a while ago where Lightroom would not know files were imported and import them again, but still linking both images to the one file. It was fixed, but this may be a hangover from that.

[Jay_Warner]

That bug you mention may possibly be blamed for the presence of the 'doubles' in the first place.  However, I did not keep any sort of record of what was being done, so have no info on that possibility.

[Jay_Warner]

I should add, that LR does not like to move those 'doubles' into another folder.  Like, it gets into a loop & everything stops moving.  Force quit is the only way I've found to get out of it.  If I move one of the pair at a time, it works OK.  HOWEVER:  whatever is done to one of the 'doubles' happens to the other as well.  If you want to keep a file, you have to Remove it, then Import/Add it back.