The error happens at various citations so I suspect it's about some random event that triggers the error in general (at which point Zotero becomes unstable) rather than a particular citation in a particular doc. But yes I will generate a Report ID next time this happens.

We need a Debug ID, not a Report ID. We don't really see anything like the bug you're experiencing so it's hard to say what's causing it from the Report ID. It would be best if you figured out the steps to reproduce the error consistently. This could be security software interfering with Zotero.

The last paragraph of the debugging page (which dstillman referred to) mentions how to generate a Report ID, this is why I linked to that as opposed to a debug ID

Sorry, I misremembered it linking to the Debug ID page.

Zotero shows a generic error message (that is often reported in this forum) when something goes wrong, but your Report ID contains a more specific error message that we don't ever see. Security software is not a "static" thing, it always updates and may start blocking something that it didn't used to block before, so this is something worth investigating.

OK, this took one whole day of work until the error happened again, and it in fact happened while I was working on a different document, which suggests this is not a document-specific error.

Debug ID: D1140086181

Thanks again for your help, I will be relieved to (try and) have this fixed!!

Ok - thanks anyway for looking into this. Word tells me it's at its latest version, Windows updates are always ongoing so I assume likewise there; and have restarted my PC countless times. My security software (Comodo) is the last suspect though, so I can try to have a few days of work with that disabled. But as I said, I'd much more strngly suspect my recent update from Office 2019 to 2021, although that leaves me with little by way of debugging this error.

Indeed, that was my experience so far as well, it's only after the 2021 upgrade that the error keeps coming back rather than happening once in a blue moon and then going away.

Thanks a lot for still helping with this, the problem is still ongoing, although it seems for some reason to happen somewhat less frequently (once every other day or so). To your questions:
- I'm pretty sure this happens also when only a single document or instance of Word is open, so having multiple docs/instances open isn't necessary
- none of my docs are on OneDrive, they are all local on my PC
- some of my folder names do contain periods (.) and hastags (#).. but again, this wasn;t different back in Word 2019, when this Zotero error was only a one-in-a-blue-moon occurrence. If you suspect this might play a role, I can certainly try to rename some folders and see if this makes a difference in the long run?

Right now, I am restarting my PC (and reopening multiple windows, programs, etc.) several times in a day, to get around this problem. If there's anything else you can suggest me to try, I'd happily do it, as I do little these days other than try and humour Zotero and/or Word into letting me get on with my work.

Restarting doesn't even help any more, so my documents are stuck, references-wise. Went through all 10 steps of the troubleshooter (https://www.zotero.org/support/kb/debugging_broken_documents), they don't help.

Sorry for taking a while to respond. I'm afraid I don't have much to say here. You are the only person reporting this issue and there are thousands of daily Zotero users with Word so this would be reported more widely if it was a bug on our part or even an issue introduced in Word that affects all users. The sporadic nature of the errors also means that they are impossible to troubleshoot in the ordinary way by us developers reproducing the bug locally and digging into the code. These errors are most likely related to something on your computer: either configuration or some software that you run. Your best bet is to tweak parts of your system: try closing programs that could interfere, reinstall software, perhaps even reinstall Windows itself.

Dear Zotero devs,
I am now getting this error ALL of the time, in every document, even after I restart my PC, and after having reinstalled the Word addin from the Z options, and also Office and Zotero themselves.
Perhaps there's something else that can be tried before I consider reinstalling Windows itself, which needless to say would be very time-consuming?
Thank you!

Thanks adomasven! Creating a new Windows account on one's PC, and configuring it so one can work on it as normal seems to be about as much trouble as reinstalling Windows, so I did some more searching for the "unhandled exception occured" error that Zotero Integration throws, as per the logs.

As per this old thread, it seems problems can emerge if either Word or Z are launched with admin privileges:
https://forums.zotero.org/discussion/86066/zotero-doesnt-start-with-word . This is easy to check: https://superuser.com/a/1213106/512216

For some reason, it seems Word 2021 on my PC is indeed launched as admin when opened via double-clicking on a document in Windows Explorer, though not when opening Word from the Start menu. And in the latter case, the error (reliably, at least in my last 10min of testing) does NOT appear, whereas it does in the former case.

So, after 2 months in which this thing stole hours from every one of my work weeks, we seem to've finally solved it. I very much hope this will save someone else going through the same trouble.

Disconcertingly, the error is still not 100% reproducible. If I open a doc via doubleclick and another via Start (one process admin, the other one not), it still does not appear. However, this may happen after some time, and would explain why initially this error was bothering me when I had 2 or more docs open, with some leaks of reference from one doc to another, as per my older thread: https://forums.zotero.org/discussion/93609/

This all also explains why rebooting sometimes (but not always) worked around the error for me, since it presumably meant in some cases I would subsequently reopen Word in the `right` way (no admin).