External disk access error with HBS3

English Backup and data protection
1

— Englische Übersetzung von Dolbyman hinzugefügt —

Hallo, ich stoße auf I/O-Fehler bei externen USB-Festplatten, die für Backups über HBS3 verwendet werden. Nach meiner Erfahrung (ich verwalte etwa sechzig NAS-Geräte) scheint das Problem nach dem letzten Update am 14. Oktober aufgetreten zu sein. Die Festplatten sind für Schreibvorgänge erreichbar, aber die Backups schlagen fehl. Hat jemand eine Idee? Könnte es sich um einen Bug in dieser Version handeln? (P.S.: Bei den USB-Backups ist die „Smart Versioning“-Funktion aktiviert.) Danke!

2

Please make sure to post in English, we do not have a French section!

3

Ok, thanks

4

Same issue here since upgeade to HBS 3 (V26.4.5.115)

Exact error msg: [Hybrid Backup Sync] Failed to complete Backup job: “Remote Backup NAS01toNAS03”. Encountered insufficient storage space or I/O error on destination device.

5

There are no release notes for HBS3 26.4.5.115

grafik
grafik1212×656 56.6 KB

https://www.qnap.com/en/app-release-notes?app=HybridBackup&product-line=nas

You can downgrade to HBS3 26.4.4.788

6

I, with the help of Claude, was able to work around this by recreating the backup to a new destination folder… My situation is a QTS → QuTS Hero.

8

I did the same with sucess. Reversing back to 26.4.4.788 is the current solution until a fix is out.

9

Reversing back to 26.4.4.788 is the current solution. I confirm !

10

Same issue here. HBS3 complains about insufficeint disk space but there are still 6 TB free on the USB disk drive (ext4). The issue appeared only for a versioned backup but not for sync jobs to the same drive.

Going back to the previous HBS3 release fixes the issue.

11

Just wanted to reply that since the HBS auto updated on 14 October 2026, all my jobs to my Wasabi bucket were failing with the vague “Message: [Hybrid Backup Sync] Failed to complete Backup job: “JOB NAME”. You do not have permission to access this file. Check access permissions.”
Downgrading to 26.4.4.788 fixed the issue, and I did not have to re-create any of the jobs.

12

Thanks for the report! We’ve confirmed this issue with versioned backups in HBS 3 26.4.5.115, and our team is working on a fix for an upcoming update. In the meantime, downgrading to 26.4.4.788, as mentioned above, works around the issue.

13

Hybrid Backup Sync repeatedly fails with the message:

[Hybrid Backup Sync] Failed to complete Backup job: “{job-name}”. Encountered insufficient storage space or I/O error on destination device.

This problem started after installing the latest HBS release (26.4.5.115).

Problem occurs when writing to both external USB hard drive and an a Remote (QNAP) NAS.

  • Destinations have sufficient space and are free of errors.
  • External USB drive was reformatted.
  • Remote NAS shared drive was deleted and recreated.
  • HBS was removed and re-installed.
  • Backup jobs were recreated from scratch.

Initial backups worked to both external and remote NAS.

All attempts at additional backups to either destination failed with same error.

Existing setup has been working for years until HBS update.

When will WORKING version of HBS 3 be released (no release notes for latest version?)

How do I install previous version of HBS 3?

14

For a intel-NAS or a TS-x73A (AMD)
https://download.qnap.com/QPKG/HybridBackup_26.4.4.788_x86_64.zip

TS-231P, …
https://download.qnap.com/QPKG/HybridBackup_26.4.4.788_arm-x41.zip

TS-233, …
https://download.qnap.com/QPKG/HybridBackup_26.4.4.788_arm_64.zip?

For other NAS i need the NAS name

15

This worked! But please note I also needed to install the previous version on the destination/target NAS when backing up to a remote NAS.

16

Hi @Becker2020, how or where do you get the previous version for a TS-855X and TS-831X.

Thanks so much

17

TS-855X Intel-NAS
https://download.qnap.com/QPKG/HybridBackup_26.4.4.788_x86_64.zip

TS-831X ARM-NAS
https://download.qnap.com/QPKG/HybridBackup_26.4.4.788_arm-x41.zip

18

You must know the version name. I have a lokal archiv

image
image545×257 13.5 KB

19

release notes for HBS3 26.4.5.115

  • HBS 3 Hybrid Backup Sync 26.4.5.115

    2026/10/05

    [Enhancements]

    - Updated Python and related third-party packages to improve stability and security.

    [Fixed Issues]

    - Fixed an issue where folders deleted from the source could fail to be removed from the destination after the next run of a remote two-way sync job.

    - Fixed an issue where folders deleted from the source could intermittently reappear after the next run of a remote two-way sync job on certain NAS models.

Release Notes for Apps | QNAP

20

Many thanks, much appreciated.