How To Resolve macOS Cloud Drive Stuck On Syncing?

You are staring at that tiny spinning icon in your Finder sidebar. It says your iCloud Drive is syncing. But nothing moves. The progress bar stays frozen. Files refuse to upload or download. You feel stuck, and so does your Mac.

This problem affects thousands of macOS users every year. Your iCloud Drive gets stuck on syncing in the background, and the usual advice of “just restart your Mac” does not always work. The issue can freeze your workflow, slow down your entire system, and leave important files in limbo between your local storage and the cloud.

The good news? You can fix this. Most iCloud Drive sync problems have clear, practical solutions that you can apply right now without losing any data. Some fixes take less than a minute. Others require a bit more patience but deliver permanent results.

This guide walks you through every proven method to resolve macOS cloud drive syncing issues. You will learn what causes the problem, how to identify the specific bottleneck on your Mac, and how to apply fixes in order from the simplest to the most advanced.

Key Takeaways

• The “bird” process controls iCloud syncing on your Mac. Force quitting this process through Activity Monitor or Terminal is often the fastest fix for a stuck sync. The process restarts automatically and usually begins syncing again within seconds.
• Check Apple’s System Status page before you troubleshoot your own Mac. If iCloud Drive servers are down on Apple’s end, no local fix will help. Visit apple.com/support/systemstatus to confirm the service is operational.
• Large or corrupted files can stall the entire sync queue. A single problematic file can block thousands of other files from uploading. Use the binary search method to identify and isolate the file causing the issue.
• Clearing the CloudDocs and FileProvider cache forces iCloud to rebuild its local sync database from scratch. This fix has resolved issues for users who had cache files ballooning to tens of gigabytes, which slowed the entire system.
• Signing out and back into iCloud is a powerful reset, but use it carefully. Always choose to keep a local copy of your files before signing out to avoid accidental data loss.
• Keeping macOS updated and maintaining sufficient iCloud storage space prevents most syncing problems before they start. A full iCloud account or an outdated operating system creates conditions where sync failures become frequent.

Understanding Why iCloud Drive Gets Stuck Syncing

iCloud Drive syncing depends on several background processes working together on your Mac. The two most important ones are “bird” and “cloudd.” These are system daemons that monitor your files, detect changes, and communicate with Apple’s iCloud servers to keep everything in sync.

When syncing works correctly, you never notice these processes. They run silently and use minimal resources. But when something goes wrong, one or both of these processes can enter a stuck state where they keep running but stop making progress.

Several factors can trigger this stuck state. Network interruptions during a large upload can confuse the sync queue. A single corrupted file can block the entire pipeline. Insufficient iCloud storage space prevents new uploads from completing. Sometimes the local cache database grows too large and becomes unreadable, which makes the system grind to a halt.

The frustrating part is that macOS does not give you clear error messages about what went wrong. You see a vague “syncing” status or an “uploading X items” message that never changes. Apple designed iCloud Drive to “just work,” so the system lacks detailed user facing diagnostics.

Understanding these root causes helps you pick the right fix. A network issue requires a different solution than a corrupted cache file. The sections below address each cause with a specific, tested solution.

Check Apple’s iCloud System Status First

Before you change anything on your Mac, verify that the problem is not on Apple’s side. Apple’s iCloud servers occasionally experience outages or performance degradation. If the servers are down, your Mac will appear stuck on syncing because it literally cannot reach the cloud.

Open your web browser and go to apple.com/support/systemstatus. This page shows the current operational status of every Apple service. Look for “iCloud Drive” in the list. A green dot means the service is operational. A yellow or red indicator means Apple is experiencing issues.

If iCloud Drive shows a problem on Apple’s status page, you do not need to troubleshoot your Mac at all. Wait for Apple to resolve the server issue. Outages typically last a few minutes to a few hours. Apple updates the status page in real time as they fix things.

You should also check your own internet connection. Open a web browser and load a few websites. Run a speed test at fast.com or speedtest.net. iCloud Drive requires a stable connection to sync files. If your internet is slow or dropping packets, syncing will stall repeatedly.

Try switching between Wi-Fi and Ethernet if you have both available. Some users have reported that having both Wi-Fi and Ethernet active simultaneously can cause timing conflicts with iCloud syncing. Temporarily disabling one connection and restarting the sync process has resolved this issue for multiple users.

Force Quit the “Bird” Process in Activity Monitor

The fastest fix for a stuck iCloud Drive sync is to force quit the “bird” process. This process is the core daemon responsible for iCloud file synchronization. When it gets stuck, killing it forces macOS to restart it fresh.

Open Activity Monitor from your Applications > Utilities folder. You can also press Command + Space and type “Activity Monitor” to find it with Spotlight. In the search bar at the top right of Activity Monitor, type “bird” to filter the process list.

Select the bird process and click the X button in the toolbar. A dialog box will appear asking if you want to Quit or Force Quit. Choose “Force Quit.” The process will terminate and macOS will automatically restart it within a few seconds.

After the restart, check your iCloud Drive status in Finder. Click the pie chart icon next to iCloud Drive in the sidebar. In many cases, syncing resumes immediately and begins making progress again.

If you see multiple bird processes listed, force quit all of them. Some users report that killing only one while others remain active can cause conflicts. The goal is to clear all instances and let macOS spawn fresh ones.

This method works because the bird process sometimes enters a deadlock state where it holds file handles open but cannot complete the transfer. A fresh start releases those locked resources and lets the sync queue process normally again.

Use Terminal Commands for a Deeper Reset

If Activity Monitor did not resolve the problem, Terminal commands give you more control over the sync processes. Open Terminal from Applications > Utilities or use Spotlight to find it.

Type the following command and press Return:

killall bird

This command terminates all running instances of the bird process simultaneously. Unlike Activity Monitor, where you might miss a process, this command catches every instance at once.

If that alone does not work, try this combined command:

killall bird; killall cloudd

This stops both the bird process and the cloudd daemon, which handles the cloud connection layer. Restarting both processes together gives the sync system a more complete reset.

For an advanced option, you can increase the priority of the bird process so your Mac allocates more resources to syncing. Type this command:

renice -10 -p $(pgrep bird)

This command raises the scheduling priority of the bird process. It tells macOS to give syncing tasks more CPU time and attention. The change lasts until your next restart, so it is safe and temporary.

You can also inspect what the bird process is doing by checking its logs. Use this command:

log show –predicate ‘process == “bird”’ –last 1h

This shows the last hour of sync activity logs. Look for lines that contain the word “error” to identify what might be blocking the sync. You can pipe the output through grep to filter results: add | grep error at the end of the command.

Clear the CloudDocs Cache Folder

iCloud Drive maintains a local cache of sync information in a folder called CloudDocs. When this cache becomes corrupted or excessively large, it can prevent syncing from completing. Clearing it forces iCloud to rebuild the cache from scratch.

Open Finder and press Command + Shift + G to open the “Go to Folder” dialog. Type the following path and press Return:

~/Library/Application Support/

Find the folder named CloudDocs in this directory. Drag it to the Trash and empty the Trash. Then restart your Mac.

When your Mac restarts, iCloud Drive will detect that the cache is missing and automatically regenerate it. This process may take some time depending on how many files you have in iCloud Drive, but it resolves many persistent sync issues.

There is a second cache location that can also cause problems. In Terminal, navigate to:

~/Library/Application Support/FileProvider/

Inside this directory, you will find folders with long UUID strings. Open each one and look inside the database subfolder. Some users have found cache files here that grew to tens of gigabytes, which made their entire system slow and unresponsive.

Delete the contents of the database folder, then restart your Mac. This forces iCloud to rebuild its file provider database. You will not lose any actual files. The database only contains local metadata about your cloud files, and iCloud regenerates it automatically.

Check Your iCloud Storage Space

A full iCloud storage account is one of the most common reasons for sync failures that people overlook. If your iCloud storage is at capacity, new files cannot upload. The sync process tries repeatedly, fails each time, and appears stuck.

On your Mac, click the Apple menu and open System Settings (or System Preferences on older macOS versions). Click your Apple ID at the top, then select iCloud. You will see a storage bar showing how much space you have used and how much remains.

If your storage is nearly full or completely full, you need to free up space before syncing can resume. Review what is consuming your storage. Common culprits include Photos, old device backups, and large files stored in iCloud Drive.

Delete unnecessary files from iCloud Drive, remove old device backups you no longer need, or consider upgrading your iCloud storage plan. Apple offers 50 GB, 200 GB, and 2 TB plans, with additional options through Apple One bundles.

After freeing space, give iCloud a few minutes to recognize the change. Then run killall bird in Terminal to restart the sync process. With available storage space, the stuck uploads should begin moving again.

Also verify that the specific files stuck in the queue are not larger than your remaining free space. A single large video file trying to upload to an almost full account will block the entire sync queue behind it.

Restart Your Mac in Safe Mode

Safe Mode is a special startup environment that disables third party extensions, login items, and non essential system processes. Starting in Safe Mode can reveal whether a background application is interfering with iCloud Drive syncing.

For Apple Silicon Macs (M1, M2, M3, M4 chips), follow these steps. Shut down your Mac completely. Press and hold the power button until you see a gear icon on screen. Release the button. Click your startup volume, then hold down the Shift key. Click “Continue in Safe Mode.”

For Intel based Macs, restart your Mac and immediately hold down the Shift key. Keep holding it until you see the login window. Log in normally. You may need to log in twice.

Once in Safe Mode, check if iCloud Drive begins syncing. If syncing works in Safe Mode but not in normal mode, a third party application or login item is likely interfering. Common culprits include antivirus software, VPN clients, and third party cloud storage apps that modify file system behavior.

To find the problematic app, restart normally and disable your login items one at a time. Go to System Settings > General > Login Items and remove items individually, testing iCloud Drive sync after each removal.

Safe Mode also clears certain system caches automatically, which can fix sync issues on its own. Even if you cannot identify a specific conflicting app, the cache clearing that happens during a Safe Mode boot sometimes resolves the problem permanently.

Identify Problematic Files With Binary Search

Sometimes a single file causes the entire iCloud Drive sync to stall. This file might be corrupted, have incorrect permissions, or contain characters in its name that iCloud cannot process. The binary search method helps you find this file efficiently.

Start by selecting half of the folders in your iCloud Drive. Tag them with a Finder color label so you can track what you moved. Drag them to your Desktop or another local folder outside of iCloud Drive.

Wait and observe if the remaining files begin syncing. If syncing resumes, the problematic file is among the folders you removed. Drag them back one at a time, checking sync status after each return. When the sync stalls again, you have identified the folder containing the problem file.

Open that folder and repeat the process at the file level. Split the contents in half, remove one half, and test. Continue splitting until you isolate the exact file that stalls the sync.

Common problem files include very large files over several gigabytes, files with special characters in their names, and zero byte files that were created during a failed previous sync attempt. Files with excessively long file paths can also cause issues because iCloud has path length limits.

Once you find the culprit, try renaming it to remove special characters. If that does not help, try re exporting or recreating the file. In some cases, you may need to exclude that specific file from iCloud Drive and store it locally instead.

Sign Out of iCloud and Sign Back In

This method is a full account level reset of the iCloud connection on your Mac. It is more disruptive than the previous methods, so use it only after simpler fixes have failed.

Open System Settings and click your Apple ID at the top. Scroll down and click “Sign Out.” macOS will ask if you want to keep a copy of your iCloud data on this Mac. Always choose to keep a copy. This protects your files during the reset process.

Wait for the sign out process to complete. This may take several minutes. Once finished, restart your Mac. After the restart, open System Settings again and sign back into your Apple ID.

macOS will begin reconnecting to iCloud Drive and reconciling your local files with the cloud versions. This process creates a fresh connection and rebuilds the sync state from scratch. It often resolves persistent problems that survived all previous troubleshooting steps.

Be patient during the re sync. Depending on how many files you have, the initial reconciliation can take several hours or even a full day. Keep your Mac powered on, connected to the internet, and avoid putting it to sleep during this period.

One important caution: during previous sync issues, some files may have become zero byte placeholders locally. After signing back in, compare important folders with a known good backup to ensure all your files have their full content intact.

Update macOS to the Latest Version

Apple regularly fixes iCloud Drive bugs in macOS updates. Running an outdated version of macOS means you may be experiencing a sync bug that Apple has already patched.

Open System Settings and go to General > Software Update. Let your Mac check for available updates. If an update is available, download and install it. Make sure you have a recent backup before updating, either through Time Machine or another backup method.

Some notable macOS updates have specifically addressed iCloud Drive sync stalls, particularly around the bird and cloudd processes. Users who experienced months of sync problems sometimes found that a simple macOS update resolved everything.

If you are several versions behind, consider updating incrementally rather than jumping multiple versions at once. This gives each update the opportunity to apply its specific fixes to your system configuration.

After updating, restart your Mac and check iCloud Drive sync status. Run killall bird in Terminal to give the newly updated sync process a fresh start. Updated processes with bug fixes applied from the start have the best chance of working correctly.

Also check for firmware updates that sometimes accompany macOS updates on Apple Silicon Macs. These lower level updates can fix networking stack issues that indirectly affect cloud synchronization reliability.

Enable Content Caching on Your Mac

Content caching is a built in macOS feature that stores iCloud data locally to reduce internet bandwidth usage. Enabling it has resolved sync issues for some users because it changes how your Mac interacts with Apple’s servers.

In macOS Ventura or later, go to System Settings > General > Sharing. Find Content Caching and click the info icon next to it. Toggle it on.

In macOS Monterey or earlier, go to System Preferences > Sharing and check the box next to Content Caching.

Content caching works by creating a local copy of your iCloud content that your Mac can reference instead of constantly downloading from Apple’s servers. This reduces the load on both your internet connection and Apple’s infrastructure.

The cache needs storage space on your Mac. If your startup drive is nearly full, you can direct the cache to an external drive using the options in the content caching settings. Apple recommends having at least 25 GB of free space available for the cache.

After enabling content caching, restart your Mac and monitor iCloud Drive sync progress. Some users report that this fix works because it essentially provides an alternative sync pathway that bypasses whatever bottleneck was causing the original stall.

This solution comes recommended by several macOS experts and has helped users who exhausted all other standard troubleshooting methods. It is safe to leave enabled permanently, as it can also speed up software updates and app downloads across all your Apple devices on the same network.

Check Your Trash for Stuck Cloud Files

A lesser known cause of iCloud Drive sync stalls is files stuck in the Trash. When you delete files from iCloud Drive, they move to the Trash and macOS must sync that deletion with Apple’s servers. If a file in the Trash has a cloud sync conflict, it can block the entire queue.

Open your Trash by clicking its icon in the Dock. Look for files that show a small cloud icon next to them. These files are still trying to sync their deletion state with iCloud.

Select these cloud flagged files and permanently delete them by right clicking and choosing “Delete Immediately” or by pressing Command + Delete. This removes them from the sync queue entirely.

After clearing these files, empty the Trash completely. Then run killall bird in Terminal to restart the sync process. Many users have reported that this simple step fixed sync stalls that persisted for weeks.

Also check if any files in your Trash are extremely large. macOS attempts to sync the deletion of large files, which can consume bandwidth and create timeouts. Clearing these files frees up the sync pipeline for your actual uploads and downloads.

Make it a habit to empty your Trash regularly, especially after deleting files from iCloud Drive. Letting deleted cloud files sit in the Trash creates unnecessary sync overhead and increases the risk of future stalls.

Disable and Re enable iCloud Drive Selectively

Rather than signing out of your entire Apple ID, you can toggle just iCloud Drive off and on. This is a more targeted reset that affects only the file sync service without disrupting your other iCloud features like Photos, Mail, or Contacts.

Go to System Settings > Apple ID > iCloud. Find iCloud Drive in the list and toggle it off. macOS will ask what you want to do with your local iCloud Drive files. Choose “Keep a Copy” to preserve your files locally.

Wait for the process to complete. This may take a few minutes as macOS removes the sync connection while preserving your files. Once finished, wait about 30 seconds, then toggle iCloud Drive back on.

macOS will begin a fresh sync, comparing your local files with what exists on Apple’s servers. This targeted reset clears the sync state for iCloud Drive specifically without affecting your iCloud Photos library or other services.

Monitor the sync progress by clicking the pie chart icon next to iCloud Drive in the Finder sidebar. You should see a file count and size indicator showing active progress. If the numbers are changing, the fix worked.

One word of caution: during this process, do not modify any files in your iCloud Drive folder. Let the sync complete fully before you add, edit, or delete anything. Changes during an active reconciliation can create duplicate files or sync conflicts.

Contact Apple Support as a Last Resort

If you have tried every method above and your iCloud Drive is still stuck, Apple Support is your final option. The issue may require server side intervention that only Apple engineers can perform.

Contact Apple Support through support.apple.com, the Apple Support app, or by calling your local Apple Support number. Explain that you have already tried basic troubleshooting including killing the bird process, clearing caches, booting in Safe Mode, and toggling iCloud Drive.

A first level support representative will likely walk you through standard steps again. If those do not work, request to be escalated to a senior technical advisor. Senior advisors have access to deeper diagnostic tools and can file engineering tickets on your behalf.

Apple may ask you to install a diagnostic profile on your Mac that collects detailed sync logs. These logs give Apple’s engineering team information about what is happening at the server level. The process of collecting and analyzing this data can take days to weeks, but it addresses problems that no user facing fix can resolve.

Some persistent sync issues have turned out to be server side problems affecting specific accounts. In these cases, Apple’s engineers fix the issue on their backend without the user needing to do anything additional. The sync simply starts working one day after the engineering team applies their fix.

Keep records of your case number and the name of your support advisor so you can follow up easily. Be patient but persistent. Check in weekly if you do not hear back. Your files are safe in iCloud even while the sync is stuck, so there is no data loss risk during the waiting period.

Frequently Asked Questions

Why does my iCloud Drive keep showing “syncing” but never finish?

The most common cause is the “bird” process entering a stuck state. This background daemon manages all iCloud file transfers. When it gets stuck, it continues to report syncing activity without making actual progress. Force quitting the process through Activity Monitor or running “killall bird” in Terminal usually resolves this. Other causes include insufficient iCloud storage space, corrupted cache files, and problematic individual files blocking the sync queue.

Will I lose my files if I clear the iCloud Drive cache?

No. Clearing the CloudDocs or FileProvider cache only removes local metadata that describes your cloud files. Your actual files remain safely stored on Apple’s iCloud servers and on any other devices synced to your account. After clearing the cache, macOS rebuilds it automatically by downloading fresh metadata from iCloud. This process may take some time but does not delete any of your documents, photos, or other data.

How long should iCloud Drive syncing normally take?

Sync speed depends on your internet upload speed and the number of files being synced. A few hundred megabytes should sync within minutes on a fast connection. Several gigabytes can take one to several hours. If your sync has shown no progress for more than 24 hours on a stable internet connection, something is likely stuck and needs troubleshooting.

Can third party apps cause iCloud Drive to stop syncing?

Yes. Antivirus software, VPN clients, and other cloud storage services can interfere with iCloud Drive syncing. These applications sometimes intercept or modify file system operations in ways that conflict with iCloud’s sync processes. Booting into Safe Mode disables these third party items and helps you determine if one of them is the cause. If syncing works in Safe Mode, systematically disable your third party apps one at a time to find the culprit.

Does restarting my Mac fix iCloud Drive syncing issues?

A simple restart fixes many sync stalls because it terminates all processes and clears temporary memory states. When your Mac restarts, the bird and cloudd processes launch fresh without any stuck file handles or deadlocked resources. If a basic restart does not work, try the more targeted solutions in this guide, starting with force quitting bird and progressing to cache clearing and account resets.