Fix OneDrive sync problems on Windows: error codes, resets and policies

When OneDrive files aren't syncing on Windows, open the OneDrive icon's Activity Center and read the error code or message first: most problems are a specific file (invalid name, path over 400 characters, a file that's open or larger than 250 GB), a sign-in or connectivity error such as 0x8004de40, or a policy that blocks the account. Fix the file or the connection, and if the app itself is stuck, reset it with onedrive.exe /reset, which reconnects sync without deleting any files. For problems across many PCs, check the OneDrive policies on the device and the sync health dashboard in the Microsoft 365 Apps admin center.

Who this is for and what you will have at the end

This guide is for service desk engineers and Microsoft 365 administrators who support the OneDrive sync app (OneDrive.exe) on Windows 10 and Windows 11 with work or school accounts. It works through the problem in the order that resolves most tickets fastest: read the error, fix the file, fix the connection, reset the app, then look at policies and fleet-wide reporting.

At the end you will have:

• A lookup table for the OneDrive error codes you are most likely to see.
• The file-level limits that silently block sync, and how to clear them.
• A safe reset procedure and what it does and doesn't touch.
• The tenant and device policies that stop sync on purpose, and how to confirm them.
• Sync health reporting so you see errors before users report them.

Before you start: collect the basics

From the affected device, note:

• The exact message or error code from the Activity Center (select the OneDrive cloud icon in the notification area).
• The OneDrive version and device ID: select the OneDrive icon, then Help & Settings > Settings > About.
• Which account is affected: a device can have one personal account and up to nine work or school accounts, and an error on one account doesn't mean the others are broken.
• Whether the user is signed in. A password change often leaves OneDrive waiting for a fresh sign-in.
• Storage. If the user's OneDrive is full, OneDrive can't upload, edit or sync new files.

Also rule out unsupported setups early. You can't use a network or mapped drive as the OneDrive sync location, OneDrive doesn't sync through symbolic links or junction points, roaming, mandatory and temporary Windows profiles aren't supported, and OneDrive can't run with elevated privileges.

Step 1: Match the error code

Microsoft maintains a list of OneDrive error codes. These are the ones that come up most often on Windows with work accounts:

Numeric codes appear too: 6 is a timeout, 36 means the SharePoint List View Threshold (about 5,000 items) was exceeded, and 49 means the OneDrive version is too old.

Step 2: Clear file-level blockers

Many "not syncing" tickets have no code at all, only a red X on a few items. These are almost always one of the following limits.

Fix paths that are too long

OneDrive pauses only the item whose path is too long and keeps syncing everything else. In the Activity Center the item shows two buttons:

• Shorten path opens Shorten this path, which lists every folder in the path and how many characters you need to remove. Edit a name until it shows "Path is short enough to sync", then select Save changes. Renaming a folder here renames it everywhere in OneDrive.
• Move file or Move folder lets you pick a location nearer the top of OneDrive. Moving up one or two levels is often enough.

When several items are affected, select Fix paths to open Fix paths that are too long to sync. Fixing a parent folder clears every item beneath it. Be careful with shared folders: renaming or moving inside a shortcut to someone else's folder changes it for everyone who uses it.

Step 3: When OneDrive is stuck on "Processing changes"

Microsoft lists five common reasons: a OneDrive file is open, a lot of files were added, a very large file was added, the user isn't signed in, or the user has just signed in or updated the PC. In the last two cases and for large batches, the fix is to wait; every file will upload, more slowly on a poor connection.

For the others:

• Close files the user finished editing.
• Move large items such as ZIP archives, long videos and Outlook PST or OST files out of OneDrive, or stop syncing the folders that hold them. Outlook data files can't be removed from sync while Files On-Demand is in use, because Outlook needs local access.
• OneDrive log files named "aria-debug" can be safely deleted.
• Open the Activity Center to see files that are open, syncing or recently synced; hidden or temporary files can also hold sync up.

If the status never clears, unlink and relink the account or reset the app (Step 4).

Step 4: Reset OneDrive safely

A reset clears OneDrive's settings and sync connections and rebuilds its local database. It doesn't delete files. During the reset, OneDrive deletes its DAT file, stores application logs in the registry and settings on disk; on restart it reloads the settings and rebuilds the DAT file, then performs a full sync.

Run the command for the install location that exists on the PC. Use the first one first:

%localappdata%\Microsoft\OneDrive\onedrive.exe /reset
C:\Program Files\Microsoft OneDrive\onedrive.exe /reset
C:\Program Files (x86)\Microsoft OneDrive\onedrive.exe /reset

Paste the command into the Run box (Windows key + R) and select OK. If Windows says it can't find the file, try the next path. If none of the paths exist, the OneDrive sync app isn't installed. After the reset, start OneDrive from the Start menu yourself.

Two side effects to warn users about: every account (personal and work) is disconnected and has to sign in again, and users who synced only selected folders must choose those folders again once the first sync completes.

Step 5: Fix sign-in and connection errors (0x8004de40)

Error 0x8004de40 shows as "Login was either interrupted or unsuccessful" and 0x8004de88 as "We can't sign into your account, please try again later". Both mean the client can't reach the cloud. After confirming the device has internet access:

1. Check TLS. Microsoft's article ties this error to the TLS 1.0 and 1.1 deprecation in Microsoft 365, so TLS 1.2 must be available. Open inetcpl.cpl, go to Advanced and make sure Use TLS 1.2 is selected, then Apply and OK. The article's own steps select the TLS 1.0, 1.1 and 1.2 check boxes; on managed devices, check that against your security baseline rather than re-enabling older protocols by hand.
2. Check cipher suites. Even with TLS 1.2 on, the cipher suite order must suit Azure Front Door. The supported suites are TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384, TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256, TLS_DHE_RSA_WITH_AES_256_GCM_SHA384 and TLS_DHE_RSA_WITH_AES_128_GCM_SHA256, and they should be at the top of the list.

Enable-TlsCipherSuite -Name "TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384" -Position 0
Get-TlsCipherSuite | Select-Object -First 5 Name

If the order doesn't change, the SSL Cipher Suite Order Group Policy setting is controlling it; fix it in the GPO instead.

3. Restart while connected to the corporate network. If that doesn't help, Microsoft's article suggests leaving and rejoining Microsoft Entra ID with dsregcmd /leave and dsregcmd /join from an elevated prompt, but only while connected to the organization's network. Treat this as a last resort on managed devices, because it affects device-based access, not just OneDrive.
4. Reset OneDrive as in Step 4.

Step 6: Fix Files On-Demand errors (0x8007016a)

Error 0x8007016a usually appears when users move or delete files. Microsoft's fix is: install Windows updates, open OneDrive Settings and clear Save space and download files as you use them, reset OneDrive, then turn Files On-Demand back on.

If the Files On-Demand option is missing on a supported Windows version, check the Windows Cloud Files Filter Driver. Its start type must be 2 (automatic):

reg.exe query HKLM\SYSTEM\CurrentControlSet\Services\CldFlt /v Start

Microsoft recommends keeping Files On-Demand enabled. The Use OneDrive Files On-Demand policy sets FilesOnDemandEnabled to 1 under HKLM\SOFTWARE\Policies\Microsoft\OneDrive; if it's disabled by policy, users can't turn it on.

Step 7: Check the policies that stop sync on purpose

Some "sync errors" are policies doing their job. All of these are configurable through Group Policy and Intune, and they write registry values you can read on the device:

reg.exe query HKLM\SOFTWARE\Policies\Microsoft\OneDrive /s
reg.exe query HKCU\SOFTWARE\Policies\Microsoft\OneDrive /s

Two notes from Microsoft's policy reference: if you set a OneDrive Group Policy and later change it back to Not configured, the registry value isn't removed and the last setting stays in effect, so set it explicitly to Enabled or Disabled. And the allow and block tenant lists take the tenant ID, not a domain name.

Tenant-wide, the SharePoint admin center Settings > Sync page has Allow syncing only on computers joined to specific domains, which takes Active Directory domain GUIDs. It applies only to Active Directory domains, not Microsoft Entra domains, so check it first when users on PCs outside the listed domains report that sync is blocked. For devices that are only Microsoft Entra joined, Microsoft recommends Conditional Access instead, which fits a device-trust model like the one in the Zero Trust remote access architecture.

Keep the sync app current

The Set the sync app update ring policy writes GPOSetUpdateRing: 4 for Insiders, 5 for Production (the default) and 0 for Deferred. Microsoft recommends a few IT staff on Insiders and everyone else on Production so they get fixes promptly.

Step 8: Watch sync health across the fleet

The OneDrive sync health dashboard in the Microsoft 365 Apps admin center shows devices with sync errors, the most common error messages, app versions and Known Folder Move status.

Requirements: sync app 22.232 or later on the Insiders, Production or Deferred ring, an Office Apps Administrator or Microsoft 365 Administrator to set it up (Global Reader and Reports Reader can view it afterwards), and devices that can reach https://clients.config.office.net.

1. In the Microsoft 365 Apps admin center, go to Health > OneDrive Sync > Setup and make sure a Tenant Association Key exists (select Generate new key if it's empty).
2. Deploy Enable sync health reporting for OneDrive to the devices. In the Intune admin center, go to Devices > Configuration, create a Settings catalog profile for Windows 10 and later, add the setting from the OneDrive category and paste the key into Sync Admin Reports. With Group Policy or the registry, set EnableSyncAdminReports to 1, for example from an elevated prompt:

reg.exe add HKLM\Software\Policies\Microsoft\OneDrive /v EnableSyncAdminReports /t REG_DWORD /d 1

3. Wait. Reports take up to three days, devices must be on for at least five hours and signed in to OneDrive, and forcing a device to report isn't supported. The older SyncAdminReports value is no longer supported.

The Issues tab lists each error message with the number of affected devices, and the Devices tab shows each device's errors, app version and last synced time. Microsoft suggests rolling the reporting setting out gradually, starting with a few test devices a day.

Troubleshooting quick reference

Checklist

• Exact error code, OneDrive version and device ID recorded.
• Unsupported setups ruled out: mapped drive, symbolic links, roaming profile, elevated run.
• File blockers cleared: names, 400-character paths, 250 GB files, 300,000 items, PST files.
• Reset done with the correct onedrive.exe /reset path, and selective sync reselected.
• TLS 1.2 and cipher suite order verified for sign-in errors.
• Files On-Demand and the CldFlt driver checked for 0x8007016a.
• OneDrive policies read from the registry and matched against intent.
• Sync health reporting enabled and the Issues tab reviewed weekly.

For new file share migrations into OneDrive, clean names and paths before the move, as described in the SharePoint Migration Tool guide, so these sync errors never reach users.

References

• What do the OneDrive error codes mean?
• Reset OneDrive
• Fix OneDrive sync problems
• Fix paths that are too long to sync in OneDrive
• Troubleshoot OneDrive stuck on Processing changes
• Restrictions and limitations in OneDrive and SharePoint
• Error code 0x8004de40 or 0x8004de88 when signing in to OneDrive
• Use OneDrive policies to control sync settings
• Allow syncing only on computers joined to specific domains
• OneDrive sync reports in the Apps Admin Center
• SharePoint limits