OneNote syncing issues are one of the most common complaints from Windows users. The good news is that most problems have a fix. This guide walks you through everything you need to know, from quick checks to deep troubleshooting, so you can get your notes syncing properly again.
Why OneNote Sync Fails in the First Place
Before jumping into fixes, it helps to understand what is actually happening when OneNote syncs. Every time you make a change, OneNote tries to push that change to OneDrive and pull any updates from other devices. When that process breaks, you see the dreaded sync error icon or just stale notes.
Common root causes include:
- A lost or unstable internet connection
- OneDrive account authentication issues
- A corrupted local notebook cache
- Storage quota exceeded on OneDrive
- Outdated version of OneNote or Windows
- Conflicts between the old OneNote 2016 app and the newer Microsoft 365 OneNote app
- Firewall or antivirus blocking OneNote’s network requests
- A notebook section that is too large or contains an unsupported file type
The key thing to understand is that OneNote syncs at the notebook level, not the section or page level. If one section breaks, it can block the entire notebook from syncing.
Check the Sync Status First
Do this before anything else. It tells you exactly where the problem is.
In the Microsoft 365 OneNote app (Windows 10/11):
- Open the notebook with the issue.
- Click the sync icon (two circular arrows) in the top right corner.
- If you see a red exclamation mark next to a notebook, that notebook has a sync error.
- Click the red icon to see the error code.
In OneNote 2016:
- Go to File > Info.
- Click “View Sync Status.”
- You will see a list of all notebooks and their sync state.
Write down the error code if you see one. Error codes like 0xE4020040, 0x8004DE86, or 0xE00015E0 each point to different causes. We cover the most common ones later in this article.
Quick Fixes to Try First
These solve the majority of sync problems. Try them in order.
Fix 1: Force a Manual Sync
Sometimes OneNote just needs a nudge.
- Press Shift + F9 to sync the current notebook.
- Press F9 to sync all open notebooks.
Wait 30 seconds after pressing. If the sync icon stops spinning and no red error appears, you are done.
Fix 2: Check Your Internet Connection
Open a browser and visit any website. If the page does not load, fix your internet first. OneNote cannot sync without a connection.
If your connection works but is slow, OneNote may time out during large syncs. Try switching from Wi-Fi to a wired connection if possible.
Fix 3: Sign Out and Sign Back In
Authentication tokens expire or get corrupted. Signing out and back in refreshes them.
In Microsoft 365 OneNote:
- Click your profile picture in the top right.
- Select “Sign out.”
- Close OneNote completely.
- Reopen it and sign back in with your Microsoft account.
In OneNote 2016:
- Go to File > Account.
- Click “Sign out.”
- Restart OneNote and sign back in.
Fix 4: Check OneDrive Storage
If your OneDrive is full, OneNote cannot push new changes.
- Visit onedrive.live.com and sign in.
- Look at the storage indicator at the bottom left of the page.
- If you are at 100% or close to it, free up space by deleting files or upgrading your plan.
Even being at 99% can cause sync failures. OneNote needs some overhead space to write temporary files.
Fix 5: Restart OneNote and OneDrive
Close both apps completely, including from the system tray, then reopen them.
To fully close OneDrive:
- Click the OneDrive cloud icon in your system tray (bottom right of the taskbar).
- Click the gear icon, then select “Quit OneDrive.”
- Reopen OneDrive from the Start menu.
- Then reopen OneNote.
Intermediate Fixes for Persistent Sync Errors
If the quick fixes did not work, these steps go deeper.
Fix 6: Update OneNote and Windows
Running outdated software is a common cause of sync failures, especially after Microsoft updates OneDrive’s API.
Update Microsoft 365 OneNote:
- Open any Microsoft 365 app like Word or Excel.
- Go to File > Account.
- Click “Update Options” and then “Update Now.”
Update Windows:
- Open Settings (Win + I).
- Go to Windows Update.
- Click “Check for updates” and install anything available.
- Restart your computer after updates.
Fix 7: Close Conflicting OneNote Versions
If you have both OneNote 2016 and the Microsoft 365 version of OneNote installed, they can conflict with each other and both try to sync the same notebook simultaneously.
Check which apps you have installed:
- Press Win + I to open Settings.
- Go to Apps > Installed apps.
- Search for “OneNote.”
If you see both “OneNote” (the Microsoft 365 version) and “OneNote 2016,” consider uninstalling one. Microsoft recommends using the Microsoft 365 version for most users in 2026.
Fix 8: Check Firewall and Antivirus Settings
Your security software may be blocking OneNote from connecting to Microsoft’s servers.
Temporarily disable your antivirus and try syncing. If it works, you need to add OneNote and OneDrive to your antivirus exclusion list. The exact steps vary by software, but generally you look for a section called “Exclusions,” “Exceptions,” or “Trusted Applications.”
For Windows Firewall specifically:
- Open Windows Security from the Start menu.
- Go to Firewall and network protection.
- Click “Allow an app through firewall.”
- Make sure both “OneNote” and “OneDrive” are checked for both Private and Public networks.
Fix 9: Clear the OneNote Cache
OneNote stores a local cache of your notebooks. When this cache gets corrupted, it causes sync errors. Clearing it forces OneNote to rebuild from scratch.
Important: Make sure your notes are backed up to OneDrive before doing this.
- Close OneNote completely.
- Press Win + R to open Run.
- Type
%localappdata%\Microsoft\OneNoteand press Enter. - Open the folder that matches your OneNote version (for example, “16.0” for Office 2016 or a folder labeled with a year).
- Delete the contents of the Cache folder inside it.
- Reopen OneNote. It will rebuild the cache by downloading your notebooks again.
This process can take a few minutes, especially if your notebooks are large.
Fixing Specific Sync Error Codes
| Error Code | What It Means | Fix |
|---|---|---|
| 0xE4020040 | Network connectivity issue | Check internet, restart router |
| 0x8004DE86 | OneDrive sign-in problem | Sign out and sign back in to OneDrive |
| 0xE00015E0 | Notebook stored in a shared location with permission issues | Check sharing permissions on OneDrive |
| 0x80070005 | Access denied, often caused by antivirus | Add OneNote to antivirus exclusions |
| 0x80048802 | Service issue on Microsoft’s end | Wait and try again later |
| 0xE40200C1 | Notebook section is too large | Split large sections into smaller ones |
| 0x8004DEB4 | Account requires sign-in again | Re-authenticate your Microsoft account |
For any error code not listed here, search for it on Microsoft’s OneNote support page. Their database is regularly updated and covers hundreds of error codes.
Advanced Troubleshooting
These steps are for situations where nothing else has worked.
Fix 10: Copy Notes Out and Recreate the Notebook
If a specific notebook keeps failing while others sync fine, the notebook itself may be corrupted on OneDrive.
- Open the problem notebook in OneNote.
- Create a brand new notebook (File > New).
- Manually copy all sections and pages from the old notebook to the new one.
- Verify the new notebook syncs correctly.
- Delete the old notebook from OneDrive.
This is tedious but highly effective for stubborn corrupted notebooks.
Fix 11: Use the OneNote Diagnostic Tool
Microsoft provides a diagnostic tool specifically for OneNote sync issues.
- Open OneNote.
- Go to Help > Contact Support (in Microsoft 365 OneNote) or File > Send a Smile (in 2016).
- In the Microsoft 365 version, you can also type “Diagnose” in the search bar at the top to find diagnostic options.
Alternatively, run a repair on your Microsoft 365 installation:
- Open Settings > Apps > Installed apps.
- Find “Microsoft 365” or “Microsoft Office.”
- Click the three dots and select “Modify.”
- Choose “Quick Repair” first. If that does not work, run “Online Repair.”
Fix 12: Check OneDrive Sync Settings
Sometimes OneDrive is paused, which stops OneNote from syncing.
- Click the OneDrive icon in the system tray.
- If you see “Sync paused,” click “Resume syncing.”
- Also click the gear icon and go to Settings > Account to make sure your account is still connected.
Fix 13: Sync a Notebook Shared by Someone Else
If the problem notebook was shared with you by another person, you may not have the right permissions to write back to it. Ask the owner to check the sharing settings in OneDrive and make sure you have “Edit” access, not just “View” access.
Preventing OneNote Sync Issues
Once you fix the immediate problem, these habits help keep things running smoothly.
Keep your notebooks organized. Notebooks with thousands of pages across dozens of sections are harder to sync and more likely to develop errors. Break large notebooks into smaller ones.
Do not embed huge files directly into OneNote. Attaching a 200MB video file to a OneNote page is asking for trouble. Store large files in OneDrive directly and just link to them from OneNote.
Use the same version of OneNote across all devices. Mixing OneNote 2016 on one machine with the Microsoft 365 app on another can create format conflicts.
Check OneDrive storage regularly. Set a reminder to check your storage every month. Running out of space is one of the most preventable causes of sync failure.
Do not rename or move notebook folders in OneDrive directly. Always rename notebooks from within OneNote, not by renaming the folder in File Explorer or OneDrive. Moving notebook folders outside of OneNote breaks the link between the app and the file.
According to Microsoft’s support documentation, most OneNote sync errors are resolved by simply signing out and back in, or by checking storage quota. These two steps alone solve the problem in about 60% of cases.
OneNote Sync Settings You Should Know About
| Setting | Where to Find It | What It Does |
|---|---|---|
| Sync this notebook now | Right-click notebook name | Forces immediate sync for one notebook |
| Sync all notebooks now | File > Info > Sync | Syncs every open notebook at once |
| Work offline | File > Info | Stops all syncing temporarily |
| View sync status | File > Info > View Sync Status (2016) | Shows sync state per notebook |
| Notebook properties | Right-click notebook > Properties | Shows the OneDrive location of the notebook |
Sync Issues on OneNote for Work or School Accounts
If you use OneNote with a work or school Microsoft 365 account, the sync behavior is slightly different. Notebooks are stored in SharePoint or Teams rather than personal OneDrive.
Common extra causes in this environment:
- Your IT administrator may have disabled certain sync features.
- SharePoint site permissions may not allow you to write changes.
- Your organization’s conditional access policy may require you to re-authenticate from a managed device.
If you are in a work environment and sync has stopped working, contact your IT support team. They can check SharePoint permissions and tenant-level OneDrive settings that you cannot access yourself.
For more information on OneNote for Microsoft 365 enterprise sync behavior, see Microsoft’s official IT admin documentation for OneNote.
When to Accept That a Note Is Stuck and Recover It Manually
If a specific page or section refuses to sync after everything you have tried, you can still recover the content.
- Open the section with the stuck page in OneNote.
- Select all the content on the problem page (Ctrl + A).
- Copy it (Ctrl + C).
- Create a new page in a different, working notebook.
- Paste the content there (Ctrl + V).
- Verify the new page syncs correctly.
- Delete the original stuck page.
OneNote also keeps a local backup of your notebooks. You can find it at:
C:\Users\[YourUsername]\AppData\Local\Microsoft\OneNote\Backups
If you need to recover a deleted or corrupted page, look here first before assuming it is gone.
Summary
OneNote syncing issues on Windows are almost always fixable. Start with the simplest solutions: force sync with Shift + F9, check your internet, sign out and back in, and verify your OneDrive storage. If those do not work, clear the local cache, check for app conflicts between OneNote versions, and look up your specific error code. For persistent problems, repair your Microsoft 365 installation or recreate the notebook from scratch.
The table below summarizes the fix hierarchy:
| Step | Action | Difficulty |
|---|---|---|
| 1 | Force sync (Shift + F9) | Easy |
| 2 | Check internet connection | Easy |
| 3 | Sign out and sign back in | Easy |
| 4 | Check OneDrive storage | Easy |
| 5 | Restart OneNote and OneDrive | Easy |
| 6 | Update OneNote and Windows | Easy |
| 7 | Remove duplicate OneNote install | Medium |
| 8 | Adjust firewall/antivirus | Medium |
| 9 | Clear OneNote cache | Medium |
| 10 | Repair Microsoft 365 | Medium |
| 11 | Recreate corrupted notebook | Hard |
Most people find their fix somewhere in steps 1 through 5. If you reach step 11, you will still recover your notes. Nothing is permanently lost as long as OneNote was able to save locally before the sync broke.
Frequently Asked Questions
Why does OneNote say “Sync Pending” and never finish?
“Sync Pending” usually means OneNote is waiting for a stable internet connection or OneDrive is paused. Check that OneDrive is running and not paused. Also check if your connection is stable. If it stays stuck, force a sync with Shift + F9. If it still hangs, try clearing the cache as described in Fix 9 above.
Can I use OneNote without syncing?
Yes. Go to File > Info and select “Work Offline.” OneNote will save all changes locally. When you reconnect, manually trigger a sync. Keep in mind that if you use OneNote on multiple devices, the offline device will not receive updates from other devices until it goes back online.
Why are my OneNote notes not showing up on other devices?
The most likely cause is that the notebook has not finished syncing, or that the other device is signed into a different Microsoft account. Make sure both devices use the same account and that the notebook shows a green checkmark sync status on the device where you made the changes.
Does deleting a notebook in OneNote delete it from OneDrive?
Closing a notebook in OneNote does not delete it from OneDrive. Deleting it from within OneNote moves it to the OneDrive recycle bin, where it stays for 30 to 93 days depending on your account type. You can restore it from the recycle bin on the OneDrive website.
How do I fix OneNote sync issues after a Windows update?
Windows updates sometimes reset firewall permissions or log you out of apps. After a Windows update, try signing out and back into OneNote, checking that OneDrive is running normally, and verifying firewall settings allow OneNote and OneDrive. If the update changed system files, running a Quick Repair on Microsoft 365 (Settings > Apps > Microsoft 365 > Modify) usually resolves it.
