Backup decryption from backup done in v12.1 not working in v12

[StanoSedliak]

Hi,

I'm using also Veeam to "migrate" VMs from one vmware VeeamA to another vmware VeeamB-> that I do a backup and I do a restore on another vmware using another Veeam.
This was all working fine but since on VeeamA I did the upgrade to v12.1 and on VeeamB I have still v12.
Now after I did the backup import from Veeam backup done in VeeamA to VeeamB, I can see the backup under encrypted backups on VeeamB as always, I put there my PW as the backup job is encrypted but now I get an error:

Failed to repair: Failed to recover key sets
Background operation job failed Error: Invalid password

Is this a know issue or it will not work until I will also update VeeamB to v12.1?
If I imported the backup on VeeamA and put the PW -> decryption is working fine on VeeamA only on VeeamB with v12 its not working.
I already opened a Veeam Case # 07040821 but they just asked for logs.

If someone had same issue or info please let me know.

[chris.childerhose]

You will probably want to update VeeamB to 12.1 as well due to the file changes with the version. Veeam is looking for 12.1 on VeeamB to be able to import.

[Gostev]

And if you read the Backup Engine section of the What's New in 12.1, you will clearly see why this happens

[StanoSedliak]

I would understand if I would get an error when I try to import the backup but it let you import the backup and it will give you error after you try to decrypt it, its a little bit confusing but ok, thank you for the information gentlemen.

[Gostev]

Right, backup format is still unchanged in 12.1 (same as over a decade ago) so there's nothing for the import process to trip over on.