OneNote: Notebooks Still Visible but Cannot Be Opened — “Item Does Not Exist” or “You Might Not Have Permission”

I'm hoping someone here can help me figure out what's happened to my OneNote notebooks and whether there's any way to recover them. I've spent the past month going back and forth with Microsoft Support, and unfortunately, I'm no closer to getting an answer than when I started.

I've used OneNote for years, primarily to develop ideas for films I'm working on. One notebook in particular, called "Ideas," contains years of writing, research, concepts, and other creative work that I haven't saved anywhere else. Losing it would be devastating, and I'm trying to exhaust every possible avenue before accepting that it's gone.

What's confusing is that the notebook hasn't actually disappeared from OneNote. I can still see it listed under my notebooks, and it even says it was last opened on June 25. But whenever I click on it, I get one of two messages:

"Sorry, something went wrong. Item does not exist. It may have been deleted by another user."

Or:

"It might not exist or you might not have permission to open it."

I haven't deleted the notebook, and to my knowledge, I haven't changed any permissions or done anything that would have affected my access to it. Initially, this was only happening with "Ideas." My other notebooks were still opening normally. But at some point, those stopped working too. Now I can't open a single notebook associated with that account, even though I can still sign in and see them listed.

For some background, I originally started using OneNote while I was in college. I used my university email address to sign in and continued using that account for years afterward. Most of my work was done through the OneNote app on my iPhone, although I also used the Mac application and, more recently, OneNote through my browser.

When I first contacted Microsoft Support, they suggested that the notebooks might be associated with my university's Microsoft 365 account and advised me to contact the university's IT department.

I did that, and the university confirmed that it has never provided OneDrive storage through its accounts, meaning my notebooks couldn't have been stored in university-provided OneDrive storage. They suggested that I may actually have been using a personal Microsoft account registered with my university email address.

This is where things get particularly confusing. I also have a separate personal Microsoft account associated with my Gmail address. I vaguely remember trying to transfer or copy my notebooks to that account at some point because I knew I wouldn't have access to my university email forever. Unfortunately, I can't remember whether I completed that process or exactly how I went about it.

So I'm now wondering whether my notebooks are still sitting somewhere in OneDrive under a different Microsoft account (despite it not appearing at all on my personal email's account), whether the links I'm seeing in OneNote are pointing to an old storage location, or whether something happened to the underlying files.

I searched my Mac for locally stored OneNote files, including the Microsoft application folders, containers, caches, and other locations where I thought the notebooks might have been saved. Unfortunately, I couldn't find anything useful. I had previously uninstalled the OneNote Mac application, so I'm not sure whether that eliminated any locally stored information.

I also still have OneNote installed on my iPhone, which is the device I used most frequently. According to my iPhone's storage settings, OneNote has approximately 47 MB of Documents & Data, although I don't know whether any of that actually contains notebook content. I found two small "Quick Notes" files, but both appeared to be blank.

I haven't deleted or reinstalled the iPhone app because I'm concerned that doing so could destroy whatever information might still be cached on the device.

I've also spent a considerable amount of time trying to get help directly from Microsoft.

My original support request was escalated to a senior advisor, but I later discovered that despite my request to reroute correspondence to my personal email, Microsoft had been attempting to contact me through my old university email address, which is no longer active. So I never received the follow-up I was supposed to get.

Other representatives told me that the OneDrive support team might have access to additional tools to investigate where the notebooks were originally stored and whether the data could still be recovered. I followed their instructions and submitted a separate request to OneDrive Support around September 17.

It's now October 17, and I haven't received a response, an acknowledgment, or even a case number for that request.

Since then, I've continued contacting Microsoft Support, but I keep being directed to different websites and support forms, many of which I've already tried. In my most recent conversation, the representative ended the chat after I asked to speak with a supervisor rather than being sent another link.

I mention all of this because I've genuinely tried to work through the normal support channels, and I'm concerned that whatever opportunity I might have to recover this data is disappearing while I wait for someone to investigate.

What I'm ultimately trying to understand is how I can find out where these notebooks were originally stored and whether the underlying files still exist.

Does the fact that OneNote continues to display the notebook names and a last-opened date mean anything? Is there a way to examine the notebook links or other account information to identify which OneDrive account originally hosted them?

I'm also wondering whether the two different error messages suggest anything about what's happening. One seems to indicate that the files no longer exist, while the other suggests I might simply not have permission to access them. Is there a way to determine which is actually the case?

And if the notebooks were associated with a personal Microsoft account registered under my old university email address, could they still exist even though that email inbox is no longer active? I can still sign in to Microsoft, which makes the situation even more confusing.

If the files were deleted or moved, I'd appreciate knowing whether there are any recovery options beyond the standard OneDrive recycle bin, especially if I can't establish which account originally held them.

I'm also interested in whether there's any safe way to inspect the OneNote data remaining on my iPhone. I don't want to risk losing a potentially recoverable local copy by following the wrong troubleshooting advice.

I realize nobody here can guarantee that the notebooks are recoverable. I'm not expecting that. But I would really appreciate some guidance from someone who understands how OneNote stores notebooks, how Microsoft personal and organizational accounts interact, and whether there's a way to trace the original storage location.

These notebooks represent years of work, and the hardest part of this experience has been not knowing whether the data is actually gone or whether I'm simply looking for it in the wrong place.

If anyone has encountered something similar or knows how to investigate this beyond the usual sign-out, reinstall, and recycle-bin suggestions, I would be incredibly grateful for your help.