Zotero 6.0.37: Library items fail to download, possible invalid server data Debug ID: 1958566534

johnkevinoregan

I'm experiencing persistent synchronization errors between two Macs:

MacBook Retina running macOS High Sierra 10.13, Zotero 6.0.37

MacBook Air running macOS Sonoma, Zotero 6.0.37

Both installations report exactly the same Zotero version. I don't recall ever installing Zotero 7 or later.

On the Sonoma Mac, my group library Sensorimotor Theory of Consciousness contains numerous recent references that do not appear on the High Sierra Mac, particularly in the collections Maths & NNs and Vision.

When synchronizing on High Sierra, Zotero repeatedly reports:

"Some data in Sensorimotor Theory of Consciousness could not be downloaded. It may have been saved with a newer version of Zotero. Other data will continue to sync."

The error output has included:

Unknown field 'PMID'

Invalid field 'publisher' for type journalArticle

I initially suspected a corrupted local database. However, I have now completely reinitialized the Zotero data directory on High Sierra and synchronized from scratch. The same errors occur with the fresh database, and some references are still missing.

I found this similar discussion from August 2025, where Dan Stillman identified and corrected invalid data stored online:

https://forums.zotero.org/discussion/125941/error-some-data-in-my-library-could-not-be-downloaded

Could my problem also be caused by invalid records on the server, or is there an incompatibility with Zotero 6.0.37?

Debug ID: 1958566534

Thank you for any assistance.

adamsmith

I'm afraid you're not going to get any support on Zotero version 6, certainly not for syncing. I understand you likely can't update on your Retina Mac, but you can't expect Zotero sync to keep working on an operating system that's 5+ years past its end of life.

johnkevinoregan

it's a pity! I was hoping since Dan Stillman seemed to have solved the problem in Aug 2025 for someone else, it might be the same issue.. (https://forums.zotero.org/discussion/125941/error-some-data-in-my-library-could-not-be-downloaded)

dstillman

It’s not the same problem. Your version is just too old to sync data from current Zotero versions.

johnkevinoregan

I'm sorry to bug you, but there seems to be a misunderstanding. I'm trying to sync data **from zotero 6.0.37** running on ventura, TO my high sierra macbook retina **also** running zotero 6.0.37. Both computers are running the same version of zotero, namely 6.0.37. I never used any other version of zotero in saving data.

dstillman

You're in a group with other people. That's where the error is coming from, as you can see in the error message. You can disable syncing for that library from the Sync pane of the preferences.

(But even saving data using the Zotero Connector directly to the online library would cause this error at this point.)

johnkevinoregan

thank you for your patience and time! However, I dont see anything about group libraries in the error messages (cf my just submitted ID 1211298657 and 2045067149) -- it's all about invalid fields in the data. Anyway it would seem odd because I'm the only person saving and accessing these entries. Why should they be readable from the zerver by zotero 6.0.37 when it's running on Ventura but not when the same version of zotero is running on High Sierra? Do you think if I updated High Sierra to Monterey (which I can just do on the macbook 2016) it might download properly off the server?

Do you think if I moved the whole group library into my personal library the problem would be solved?

And do you think if I updated to Monterey on the 2016 macbook, this would solve the problem, or would I have to update to zotero 7 or higher on both?

Really sorry to keep pestering you. (I have to say that I use zotero every day and I find it is one of the best softwares I've ever used, and I congratulate you for all the work that you do on it).

adamsmith

"Sensorimotor Theory of Consciousness " is the group name in the error message