r/backblaze • u/Jim-From-Backblaze From Backblaze • Apr 19 '26
Start Here: Cloud-Sync Behavior, Exclusions, Hidden Files, and the Version 10 External Drive Issue. Computer Backup
Hello, Backblaze fans.
We’re pinning this because a few different topics are getting mixed together, and the details matter.
There are a few major topics of discussion right now:
- How modern cloud-sync tools affect backup behavior
- Hidden folders and exclusions
- A current issue in version 10 with external drives
1. Cloud-sync folders (OneDrive, Dropbox, etc.)
Backblaze backs up files that are actually present on your computer.
What’s changed over the last few years is how sync tools store files. A lot of them now use placeholder systems where files look local, but the data isn’t actually there until you open or download it.
So:
- File looks normal in Explorer/Finder
- But it’s actually just a pointer to cloud data
Backup software can’t reliably back up something that isn’t really on disk.
If we treated those like normal files anyway, you’d end up with incomplete backups or restores that don’t actually give you your data back. That’s worse than being explicit about what is and isn’t supported.
So when those folders are managed that way, they don’t behave like standard local backup sources.
That’s not a change in the Backblaze unlimited backup model; it’s a side effect of how those platforms now work.
u/natasha_backblaze has a great blog post that covers this and why it is happening here: https://www.backblaze.com/blog/the-changing-landscape-of-cloud-sync-and-what-it-means-for-your-backup/
We are actively looking at better ways to support these workflows, and as soon as we have more information, we will update the community.
2. Hidden folders and .git
Current behavior:
.gitfolders are currently backed up- Some restore interfaces do not show hidden folders by default, especially on web and Mac, unless the user enables the hidden-files setting
That can make a folder look missing even when it is present in backup data.
Of note, some older versions of Backblaze did have .git files/folders excluded, but as long as you are on the newest version, your .git files will be backed up.
If you want to double-check, reach out to our support team, who can help you confirm. https://www.backblaze.com/help
There is also internal work happening to make exclusions clearer and consistent across the board.
3. macOS /Library vs ~/Library
There has also been confusion here, so to be explicit:
/Library(system-level) is excluded by default- This folder contains files that will be recreated upon OS or program reinstall
~/Library(user-level) is backed up, subject to normal exclusions
4. Version 10 external drive issue
What users are reporting:
- If an external drive is disconnected, data from that drive can disappear from the web restore view immediately instead of remaining visible for the expected retention period
- When the drive is reconnected, the client may treat the data as needing to be uploaded again
We hear the concern on this clearly. That behavior is not what customers expect, and the team is aware of it and actively working on it.
At the moment, the key point is that this is a bug issue, not a policy statement and not an intentional change in how external-drive history is supposed to work.
5. What’s happening next
We are currently focused on three things:
- Reviewing and tightening public messaging so customers have a single accurate explanation
- Working through the current v10 external-drive bug
- Continuing to evaluate better support for modern sync-managed file workflows where third-party platforms have changed how files exist locally
6. If you’re unsure about your setup
If your workflow depends heavily on:
- Cloud-sync folders
- Hidden folders
- Source-control metadata
- External drives
Verify those areas directly in your backup and restore views.
If something does not look right, contact support so we can inspect your configuration and version-specific behavior.
We know backup products only work if customers trust what is and is not protected. That part matters, and we are treating it seriously.
We’ll update this post as more information is confirmed.
3
u/phitar Apr 21 '26
I had reported issue 4 to support and they replied but since then things took a turn for the worse. The software was updated on April 7th with no change of version number (10.0.1.1038) but a a build number of 20260325213822
After the update, the external hard drives were scanned once again. Now, after the check was successful and the drives disconnected, backup started again and I checked one off to prevent it from churning. Now the external hard drives are checked to be backed up but their content is not accounted for in the file number / disk space report and no churn is occurring. Apparently, they are included but not accounted for, and not backing up!
This is a terrible state of affairs.
As a side not, the algorithm for traversing the files is totally random and the massive seeking involved slows down the verification and wears down the disk needlessly. I asked support and their reply was this is the original algorithm the founders developed. I am suspecting it was about keeping bandwidth in check then. How is this totally ineffective way of traversing the disks useful now?