Microsoft Fixes Word Bug That Saved SharePoint PDFs to Local Cache

Have you saved a PDF from Word to SharePoint in recent weeks only to find it nowhere to be found? It’s not your fault... and that file may be sitting in a hidden folder on your PC. Microsoft has fixed the bug, but any files already misplaced have not been moved. Here’s what you need to know.

Since version 2609 of Microsoft 365 Apps for Windows (build 16.0.20430.x), Word had a nasty habit of losing track of some PDFs. More specifically, it would save your documents in an unexpected and unwanted location. This happens when a user goes through Save or Save As, chooses the PDF file type, then selects a SharePoint Online location. In that case, Word shows no error at all... but the file never reaches its destination!

Microsoft acknowledged the issue on this page on its support site. Instead of being sent to SharePoint, and therefore to your Cloud storage, the PDF is written locally to the following folder: C:Users<nom-utilisateur>AppDataLocalMicrosoftWindowsINetCacheContent.MSO, with a random filename. Yes, because apparently that would be too easy to find.

This is a real problem, because the user thinks the document was uploaded to SharePoint, but when colleagues open the online library, they won’t find anything! Searching by the document title doesn’t help either, since the PDF is accessible only locally on the user’s machine and has a name such as 1f10f000 or 458d72b7.

Microsoft only mentions the case where the document is exported to SharePoint. However, some users report the same behavior when the target is a network drive. For now, this second scenario has not been confirmed by Microsoft. The first one, however, has been fixed.

A server-side fix has been deployed

Microsoft considers this issue resolved; it was fixed directly by the Redmond company. "This issue was fixed by a service change fully deployed on September 25, 2026.", Microsoft states in its September 29, 2026 update.

In other words, there is no need to install a new build or roll back to version 2608. Microsoft simply recommends that users who are still experiencing the problem close all open Office applications, then restart Word so the change takes effect.

There is still one issue, though: PDF files created before the fix was deployed are still where Word left them, namely in the local cache. So documents that were supposed to be stored on SharePoint are not there, and the user probably does not know it. Beyond that, a copy of the document, potentially confidential, ends up on the workstation, outside the SharePoint perimeter (access rights, versioning, retention).

How can you find the missing PDFs?

If you exported PDFs to SharePoint from Word in recent weeks, take a few minutes to check.

• Check the version: in Word, open File, then Account, and look at the About Word section. A version 2609 with a build number starting with 20430 corresponds to an impacted version.
• Open the cache folder: in File Explorer, paste %LOCALAPPDATA%\Microsoft\Windows\INetCache\Content.MSO into the address bar, then press Enter.
• Sort by date: sort the contents by modification date and open the files created around the time you saved the PDFs.
• Put the files back in the right place: rename the files, upload them to SharePoint, then delete the remaining cache copies, especially if they contain sensitive documents.

Because this is a cache, it will eventually be purged. And when that day comes, the PDFs will be gone for good.

Florian Burnel Co-founder of IT-Connect

Systems and network engineer, co-founder of IT-Connect and Microsoft MVP "Cloud and Datacenter Management". I'd like to share my experience and discoveries through my articles. I'm a generalist with a particular interest in Microsoft solutions and scripting. Enjoy your reading.

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