Backups fail to upload

Configuration
1

For about two weeks my daily backups fail and I cannot find any reason for it. The log shows:

Logger: homeassistant.components.backup
Source: components/backup/manager.py:654
Integration: Backup ([documentation](https://www.home-assistant.io/integrations/backup), [issues](https://github.com/home-assistant/core/issues?q=is%3Aissue+is%3Aopen+label%3A%22integration%3A+backup%22))
First occurred: 11:25:42 (2 occurrences)
Last logged: 11:25:42

    Upload failed for cloud.cloud: Failed to upload backup Failed to upload: (400) The MD5 checksum you specified did not match what we received. You provided a MD5 checksum with value: x Actual MD5 was: y
    Upload failed for onedrive.x: Hash validation failed, backup file might be corrupt

I don’t think its the same issue as #175573 since sometimes, especially when I trigger the backup manually, it works.
Sometimes it uploads to NabuCasa but not OneDrive, sometimes the other way around, sometimes both work.

The strange thing is that the Google Backup add-on sees the update HA creates and uploads it to GDrive without any issue.

I have tested a restore of the backup, it ‘kinda’ works, I got some errors related to missing files that were included in configuration.yaml and history was not restored.

The only change I did to my env is that I increased ram from 2 to 4GB.

Any help is appreciated.

2

this is driving me insane.

It had issues on 8.1
It worked flawlessly on 8.2
The issue is back on 8.3

I cannot wrap my head around what is going on.

3

My backups work fine to a NAS. Have yet to get cloud to work for me.

Restores on the other hand are completely useless at the moment for me…

4

I have the same issue; cloud backup fails, NAS and local are OK.
Some hint about this issue?

  1. Installation method Home Assistant OS
  2. Core 2026.9.1
  3. Supervisor 2026.08.0
  4. Operating System 18.2
  5. Frontend 20260826.6
    Thank for any return
    regards! JC
5

So one morning all my history was gone following a purge. This led me to create a new VM and to try to restore from backup, but the backup was done after the purge.

Luckily for me I had a backup done with the Google Drive Addon that was 1.5 days old.

So started blank HA, installed the addon, downloaded the backup locally and restored.

Since then, the backup works fine - I got no more errors and I also tested the restore on a test VM, all good.

My guess is that something corrupted on the initial VM which was 5 years old.

I have the same issue; cloud backup fails, NAS and local are OK.

I wouldn’t be so sure, test a restore of those backups on a separate VM. The backups done by HA were useless to me, the Google addon one saved my ass.