Dropbox smart sync still taking up space

As explained by Dropbox, Smart Sync is a feature "that helps you save space on your hard drive. Access every file and folder in your Dropbox account from your computer, using virtually no hard drive space. ... With Smart Sync, content on your computer is available as either online-only, local, or in mixed state folders."

Last night and this morning, I moved a large quantity of files from an external disk into Dropbox folders on my MacBook (MacOS Mojave Version 10.14.4), then selected those Dropbox folders to be "online-only". The files rather quickly synched with Dropbox on the cloud -- I saw them appear in the local folders of a desktop computer that shares the dropbox -- but the grey icons (for "online only") took a long time to display in Finder. (More than twenty hours later, two larger folders still show the blue icon, for "synching", even though their contents have long appeared on the other computer.)

With growing alarm, I watched as each new directory added to Dropbox ratcheted up the amount of space used on the MacBook to dangerous levels (93%) even as large directories marked as "online only" continued to sync to the Dropbox cloud. I could only restore available space by moving some content back to an external disk.

Confusingly, information about how much space really remained was inconsistent. df showed 58 GB available:

Filesystem    1G-blocks       Used  Available Capacity Mounted on
/dev/disk1s1        465        403         58      88% /

while About this Mac => Storage showed 232 GB available.

According to one source, "the Storage tab in About This Mac ... can be useful as it is the only guide to what types of data are taking up storage space, but when you want to know how much space is used or free on any volume or disk, use Disk Utility: it’s much more likely to be accurate." Confusingly, however, my Disk Utility displayed both results:

• 433.68 GB used, 3.95 GB on other volumes, 62.45 GB free
• Capacity 500.07 GB, Available: 232 GB (169.55 GB purgeable), Used: 433 GB

As explained by Dropbox, "setting files to be online only will free up space on your hard drive within minutes (as long as your computer is online and able to sync to Dropbox). However: ... macOS 10.13 (High Sierra) uses ... APFS. With APFS, the operating system takes snapshots of the file system and available hard drive space. These snapshots may not update after you've used Smart Sync to set Dropbox files as online only. This means that hard drive space you freed up with Smart Sync may not be immediately reflected or available if this snapshot hasn't updated. This hard drive space should eventually be freed up by the OS, but the amount of time this will take can vary. This isn't a behavior specific to Dropbox, but instead the designed behavior of macOS." On APFS, the placeholders for "online-only files use a small amount of space on your hard drive to store information about the file, such as its name and size. This uses less space than the full file." Indeed, files marked as "online-only" continue to show their non-zero (online) sizes (e.g., with ls and os.path.getsize()) as if they were still available locally.

I gather this is a MacOS (i.e., APFS) issue, not specific to Dropbox.

My question: If Disk Utility shows 232 GB "available" but only 62.45 GB "free", what are the consequences? Would bad things happen if I were to add another 100 GB of files to the disk?

I am of course reluctant to add more content than space free just "as an experiment" but see how this could happen unintentionally.

After upgrading to Dropbox Plus, with 2TB of space, I just transferred a lot of files and folders into my Dropbox. I thought they would automatically be online-only, but when they started to sync they have almost totally filled my hard drive. I cannot change anything to "online-only." That option is not available to me. I have tried it after Pausing Sync and that did not change anything. And only have selective sync available under preferences, please help, thanks in advance.

Sometimes, you may encounter the Dropbox Smart Sync not working issues like the user, what should we do to fix it? Don’t worry, we will explain for you.

Overview for Drobox Smart Sync

Dropbox Smart Sync is an advanced feature that helps you view, access Dropbox files and folders from your computer, while using virtually no hard drive space. It is available in Dropbox Plus, Professional, Standard, and Advanced for individuals and business teams.

You may meet the following Dropbox Smart Sync not working problems while using Dropbox, find solutions respectively, or you can turn to a free alternative with powerful functionality and wider application range:

Case 1. Dropbox Smart Sync not showing up

If you connected a personal Dropbox account, Smart Sync won't be available for that personal account. Or the Smart Sync isn’t here in your Dropbox Plus, or others.

Solution: update the desktop app and Mac app to the same as well if you just upgrade Dropbox account to Dropbox Plus, or other editions in dropbox.com.

Case 2. Dropbox Smart Sync online only not working

Sometimes, you may find the Smart Sync online only not working, because the smart sync files downloaded unintended.

Solution: Make the files online-only again. Right click the file, and select Smart Sync > Online Only.

Case 3. Dropbox Smart Sync not freeing up space

If your Dropbox is full or show low disk space due to the Dropbox documents. You have to free up space.

Solutions: The two ways: Selective Sync and Delete files, could help you to free up space. Here we are going to show you about the selective sync to free up space for you hard disk.

1. Click Dropbox icon on the Windows tray, click your account profile icon, and select Preferences.

2. At the Sync tab, press Selective Sync and then Uncheck the folders and files that you would like to remove from your computer but still on your dropbox.com. Press Update to confirm. 

Case 4. Dropbox Smart Sync unspecified error

The Dropbox Smart Sync issues usually occurred while opening Microsoft Office files, words, excels, and PowerPoint.

Solution: Set the Smart Sync to Local. Here are the steps: Right click the file or folders, select Smart Sync, and then choose Local, open the files or folders when it’s downloaded.

Case 5. Smart Sync is experiencing an issue 

And there are some reasons should be responsible for this issue: Some updates happened to the Dropbox; Lack of Windows security updates; Antivirus or Security software maybe blocked the Dropbox; Something required for Smart Sync is not installed or running properly; Software conflicts.

Solutions: 

1. Add Dropbox to White-list in Antivirus or Security Software.

2. Install Windows latest updates.

3. Restart the computer and Dropbox desktop app.

4. Reinstall Dropbox with Admin privileges.

5. Disable all running software to fix the conflict (like HIBUN software, etc.).

Case 6. Dropbox Not Syncing

Besides, another issue like Dropbox not syncing maybe disturb you while syncing data to Dropbox. First ensure your computer, phone, tablet is connected to Internet, signed in the same Dropbox account, and the files or folders are located in Dropbox folder. If all is right, please refer the following solutions:

1. Rename File name without these characters: / \ < > : “ | ? * . and shorter than 255 characters.

2. Do not sync some system files and temporary files like desktop.ini, thumbs.db, *.tmp, ~file, etc.

3. Change the file location to make the file components less than 300 components.

Dropbox Smart Sync Free Alternative - AOMEI Backupper Standard

If you have problems with sync files to Dropbox with Smart Sync, you may want to try a powerful file sync software - AOMEI Backupper Standard. It is designed for Windows computers (Windows 11, 10, 8.1/8, 7, Vista, XP) to sync files to cloud (like Dropbox, Google Drive, OneDrive, Box, etc.) with simple clicks. You can also choose other devices as source or target location, such as internal/external drive, USB flash drive, NAS and network share.

It’s highly recommended by million of users over the world due to its reliable synchronization, intuitive interface and outstanding performance. And now you can simply download this freeware to enjoy the file sync feature: 

You could enjoy the following sync features:

1. Schedule sync. It allows you sync files to Dropbox or other clouds via daily, weekly, monthly, USB plug in, etc.

2. Sync Settings enables you to comment the sync task to differ from others, enable email notification to get the SMS or email alert after the sync finished, run specified program before the sync, etc.

3. One-way sync function can greatly protect the data on the source path.

4. Multiple Sync destination selection: apart from clouds, you could also sync files to external hard drive, USB drive, SD card, network share or NAS, local disk, etc.

5. Event Triggers Sync: you could trigger the sync task by the four events: user logon, user logoff, system startup, system shutdown. And you could sync files to Dropbox without occupy your working time.

6. Real time sync: It allows you to real-time monitor the source directory needing sync. If there is any change happens to any file or folder in the source directory, the program will sync them to the Dropbox immediately.

The last two are premium features, please upgrade to AOMEI Backupper Professional or other advanced editions to enjoy.

Bonus Tip: Backup Files to AOMEI Cloud

Besides Dropbox, you can also sync your files to Google Drive, OneDrive and other cloud drives using the above method. But almost all of these cloud drives only provide a few GB of free storage space. In this case, I suggest you can backup your files directly to AOMEI Cloud. After you sign up for an AOMEI account, it will provide you with 1TB of free storage for 15 days. And the process is automatic, so you don't need to worry about losing your data because you forget to backup.

Conclusion

If you meet the Dropbox Smart Sync not working problem or Dropbox not syncing files, you could try the best Dropbox alternative - AOMEI Backupper Standard to sync files to Drobox easily to safeguard all your files and folders. You can even sync open files without efforts.

Besides, AOMEI Backupper is also backup and restore software, which allows you to backup data to an image file to anywhere else you specified, create system backup for Windows PCs to prevent system boot failure, backup entire hard disk to other place just in case you need to restore everything, etc.

Why is Dropbox taking up space on my hard drive?

How do I turn off Dropbox Smart Sync?

Why is Dropbox saying I don't have enough space?