OneDrive Sync Pending Forever: How to Identify Which Sync State Is Actually Stuck

Quick answer

OneDrive showing “Sync pending” for hours doesn’t mean one thing — it means at least four different things, and they each have different fixes. Before you do anything, identify which state you’re in: stuck on a single hidden temp file, stuck “Processing changes” with no specific file, stuck on a file that’s too large or has a forbidden character, or stuck because the sync engine itself is broken. Apply the wrong fix for the wrong state and you’ll burn an afternoon. The diagnostic order is in the Common causes section. Skip ahead if you already know which state you’re in.

Before you start

Read this first. The reason most “OneDrive stuck on sync pending” guides don’t fix the problem is that they treat “sync pending” as a single symptom and offer the same listicle of fixes regardless of cause. The four sync states that present as “pending” have meaningfully different root causes, and applying the universal “reset OneDrive” advice to a single problem file is the slowest possible way to fix it.

Back up anything in your OneDrive folder that you’ve worked on recently and is not yet confirmed synced. None of the steps below should cause data loss, but if your sync was already in a degraded state when this started, the wrong intervention can compound it. The safest thing is to copy recent work to a folder outside OneDrive before you start changing things. You can move it back when sync is working again.

If you’re seeing actual error codes rather than just a “pending” status — particularly 0x8004de40 or 0x8004de90 — stop reading this guide and go to the OneDrive 0x8004de40 fix instead. “Sync pending forever” is the symptom when there is no error code; if you have a code, the code is more diagnostic than the symptom.

What this means

OneDrive’s status icons in the system tray and File Explorer report progress through several sync states: queued, uploading, processing changes, paused, synced (the green tick), errored, or pending (the blue circular arrow icon). “Pending” is supposed to be a brief transitional state — a file is queued for upload but hasn’t started yet. When a file or folder shows “pending” for more than a few minutes, something has gone wrong upstream of the upload itself.

The reason “pending” is a confusing symptom is that the OneDrive client uses the same icon for at least four different stuck conditions. The icon doesn’t tell you which one you’re in. The diagnostic information lives elsewhere — specifically in the activity center, in File Explorer’s hidden items view, and in the OneDrive client’s logs.

This is what most fix guides get wrong. They jump to “reset OneDrive” or “reinstall OneDrive” as a universal solution. Resetting OneDrive does fix some causes, but it also restarts a multi-hour re-sync of every file in your account, so it’s a last resort, not a first one.

Where this appears

You’ll see “Sync pending” in two places: the OneDrive cloud icon in the system tray (showing a small clock or arrows overlay), and the per-file/per-folder status icons in File Explorer (showing a blue circular arrow next to files in your OneDrive folder). The system tray sometimes shows “Processing changes” instead, which is a related but distinct state.

This affects:

  • OneDrive personal accounts on Windows 10 and 11.
  • OneDrive for Business work and school accounts.
  • OneDrive on macOS (with slightly different icons but the same underlying states).

Mobile OneDrive doesn’t surface these states the same way and rarely gets stuck in this manner.

Common causes

The four states. Identify which one before you do anything.

State 1 — Stuck on a single hidden temp file. The most common cause, and the most easily missed. Office applications create hidden lock files (filenames starting with ~$ or extensions like .tmp) when documents are open. If a document was open when sync started, OneDrive cannot upload the lock file, but it also can’t move past it. Visible in File Explorer only if “Hidden items” is enabled.

State 2 — Stuck “Processing changes” with no specific file shown. This is the OneDrive client’s enumeration phase taking far longer than expected. It happens when the client is scanning a folder with many tens of thousands of files, when there’s a Files On-Demand cache inconsistency, or when the file system has permissions that OneDrive can’t read. Distinguished from State 1 because no individual file is flagged in the activity center.

State 3 — Stuck on a single file that violates OneDrive’s rules. Files larger than 250 GB, files with forbidden characters in the name (< > : " | ? * #), files at paths longer than 400 characters, or filenames Microsoft has explicitly reserved (CON, PRN, AUX, etc.) cannot upload. The client tries, fails silently, and shows the file as pending.

State 4 — The sync engine itself is broken. Sign-in token has expired and the client hasn’t picked up that it needs to re-auth. Files On-Demand driver state is inconsistent. The OneDrive process has hung. Or — the deepest version — the local sync database is corrupted. State 4 is when nothing else explains it: no temp files, no oversize files, the activity center is empty, but the icon never goes green.

A small fifth cause exists and is worth flagging: if your organization has run out of storage, has had a billing failure, or has had your account suspended, OneDrive can show “pending” indefinitely. Sign in to OneDrive on the web; if the web shows storage full or account frozen, no client-side fix will help.

Fixes to try first

Diagnose first, fix second. The diagnostic takes ninety seconds.

Diagnose: which state am I in?

  1. Open File Explorer, navigate to your OneDrive folder, and turn on hidden items: View → Show → Hidden items.

  2. Click the OneDrive cloud icon in the system tray. Look at the activity center. If it lists specific files with errors or pending status — note the filenames. This tells you whether you’re dealing with a specific-file problem or an everything-is-stuck problem.

  3. Sort your OneDrive folder by status (right-click in column headers → More → tick Status). Look for any file showing the blue pending icon while everything else around it is green.

If you found a specific file or files in either step 2 or step 3, you’re in State 1 (if they’re hidden temp files starting with ~$ or .tmp) or State 3 (if they’re real files with unusual names, very large sizes, or special characters).

If nothing specific is flagged, the activity center says “Processing changes” or shows no errors, but the icon won’t go green — you’re in State 2 or State 4.

Fix State 1 (hidden temp files)

Close every Office application — Word, Excel, PowerPoint, OneNote — completely. Confirm none are running in Task Manager. Then go back to your OneDrive folder with hidden items visible, and delete any files starting with ~$ or ending in .tmp that Microsoft’s documentation specifically calls out as safe to remove. These are lock files for closed documents and Windows will recreate them when needed. Within thirty seconds OneDrive should clear the pending state.

Fix State 2 (processing changes, no specific file)

Wait first. If you’ve recently signed in, paused and resumed sync, or made bulk changes (moved a large folder, restored from backup), OneDrive’s enumeration phase can legitimately take an hour or more on accounts with many files. Microsoft explicitly notes this for macOS Big Sur and large Windows accounts. Watch the activity center; if the count of files being processed is decreasing, even slowly, leave it alone.

If the number isn’t moving:

  1. Pause sync (cloud icon → Pause syncing → 2 hours), wait a minute, then resume. This forces a re-enumeration.
  2. If that doesn’t move it, restart the OneDrive process: cloud icon → Quit OneDrive, wait fifteen seconds, relaunch from the Start menu.
  3. Check disk space. OneDrive needs working room — if your local drive is more than 95% full, sync stalls.
  4. Disable Files On-Demand temporarily (Settings → Sync and back up → Advanced settings → Free up space → Files On-Demand), let everything download to local disk, and see if sync progresses. If it does, Files On-Demand cache state was the problem; you can re-enable it once everything is synced.

Fix State 3 (specific file violates rules)

Identify the offending file from the activity center. Check it against Microsoft’s restrictions: file size, name length, forbidden characters, reserved names, path length. Rename, shorten, or move the file out of OneDrive entirely. Once removed, sync should clear within a minute.

If the file appears to follow the rules but still won’t sync, try renaming it with a brand-new simple name (like test.docx). If that works, the original name had something OneDrive doesn’t tolerate that you can’t see.

Fix State 4 (sync engine broken)

This is the only state where “reset OneDrive” is the right answer.

  1. Win+R, paste %localappdata%\Microsoft\OneDrive\onedrive.exe /reset, hit Enter. Wait two minutes.
  2. If OneDrive doesn’t auto-relaunch, start it from the Start menu manually.
  3. Sign in if prompted.
  4. Wait. A reset triggers a full re-scan of every file in your OneDrive. On accounts with tens of gigabytes, this can take hours. Don’t reboot or do anything that might interrupt it.

If reset doesn’t fix it, the next step is to unlink and re-link the account. Settings → Account → Unlink this PC, then re-set up. This is more invasive than reset (it forces re-download of files marked online-only) but resolves the deepest sync database corruption.

Advanced fixes

If you’ve worked through the four states and you’re still stuck, the remaining causes are admin-side or environmental.

Check OneDrive folder permissions. Right-click your OneDrive folder → Properties → Security. Your user account should have Full control. If it doesn’t — particularly on machines that have been migrated between user profiles or had Windows reinstalled over an old profile — the OneDrive process can’t read all the files and sync stalls. Restoring full control to your account fixes it.

Disable Office Upload Center / cloud upload. OneDrive on Windows shares state with Office’s autosave system, and a broken Office Upload state can hold OneDrive sync hostage. Open any Office application → File → Account → Sign out, then sign back in. This clears Office’s separate upload queue.

Check service health. If multiple users on the same tenant are seeing stuck sync, log in to the Microsoft 365 admin center and check Health → Service health for any active SharePoint Online or OneDrive incidents. Don’t waste hours fixing a working client when Microsoft has acknowledged a back-end issue.

Examine the OneDrive log. OneDrive writes verbose logs to %localappdata%\Microsoft\OneDrive\logs. The recent ODL files contain the actual reason sync is failing. They’re not pretty to read, but searching for ERROR or specific filenames quickly identifies what OneDrive thinks is wrong.

If you are on a work or school device

If you are not the admin and you’ve worked through States 1-4 without resolution: send your IT person this article along with a note saying “I’m stuck in State [N].” That description is more useful than “OneDrive is broken” — it tells them where to look. If they need to investigate from the admin side, point them to the SharePoint and OneDrive admin guide for the corresponding admin-side diagnostic path.

If you are the admin: a single user with sync pending forever is almost always a client-side State 1-4 problem. Multiple users on the same tenant with simultaneous sync issues is almost always service health, a tenant-wide policy change (Conditional Access tightening, retention policy changes), or a SharePoint-side storage allocation issue. Diagnose by user count first — that tells you which side of the problem to investigate.

When to stop

Stop and use the web version if any of the following apply.

You need a specific file urgently and you’ve been at this for more than thirty minutes. Sign in to onedrive.live.com (personal) or your tenant’s OneDrive web (work), download the file you need, and continue with your day. Fix the desktop client when it doesn’t matter what hour it is.

You’ve reset OneDrive and unlinked-and-relinked, and you’re still stuck. The remaining options are admin-side, service-health-side, or a system-level Windows problem (corrupt user profile, failing storage, broken Files On-Demand driver). Spend the time on diagnostics, not on more retries of the same fixes.

You’ve started seeing odd behavior beyond OneDrive — File Explorer freezes, other cloud sync apps misbehaving, system slowness. The problem isn’t OneDrive at that point; OneDrive is just the loudest symptom. Investigate the system before you keep fixing the OneDrive client.

You’re on a work device and your IT admin has told you to stop. They have visibility into causes you don’t.

  • OneDrive error 0x8004de40 — connectivity error, OneDrive can’t reach the cloud at all.
  • OneDrive error 0x8004de90 — provisioning error, OneDrive reaches the cloud but your account isn’t fully set up.
  • Sync conflict files: which version should you keep? — when sync resumes and you have duplicate “conflict copy” files.
  • Recover a deleted OneDrive file — if a sync conflict has caused a file to disappear locally.

Official references

FAQ

How long is “too long” for sync pending? For a small folder change (a few files modified), more than a few minutes. For a large folder change (moving many files, restoring from backup), several hours can be normal. For a fresh sync setup on an account with many files, the initial enumeration can legitimately run for a day. Watch the file count in the activity center — if it’s decreasing, even slowly, leave it alone.

Will resetting OneDrive delete my files? No. The /reset command clears local sync configuration, not your data. After reset, OneDrive will re-scan everything and re-sync. Files marked “online-only” will need to re-download to your device, which can take time on slow connections, but they aren’t deleted.

Why does OneDrive on the web work but the client doesn’t? The web version uses your browser to talk to Microsoft’s servers and doesn’t share the local sync engine, sync database, or Files On-Demand driver with the desktop client. Working web means your account, network, and Microsoft’s servers are healthy — the problem is local to the desktop client.

I have hundreds of files showing pending — should I delete them? No. Deleting locally during a stuck sync state can create sync conflicts or propagate the deletion to the cloud once sync resumes. Diagnose the sync state first, fix the underlying cause, then let OneDrive resume normally.

My sync is pending and I can’t open the OneDrive activity center. Help? Restart the OneDrive process: Task Manager → find OneDrive → End task, then relaunch. If unreachable repeatedly, you’re likely in State 4 — proceed with the OneDrive reset.

Should I just uninstall OneDrive and start over? Almost never. Uninstalling does the same thing as /reset but with extra steps and a longer re-sync. Uninstall is right only when your installed version is more than a year old or visibly corrupted.

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