This is a common error, if you changed your datastore name or configuration without saving your encryption keys.
The error message is clear : manifest was created with key […] which means that currently, the configured key is not the same that created the backup file you are trying to read.
As said in our documentation here, it’s very important to save your encryption key out of your Proxmox VE server. As a reminder, no one knows about backup encryptions keys except your PVE server or cluster.
Unfortunately, if you did not save your keys in advance, you have to restart a full backup job but if you get this error message it’s probably that you tried to restore a backup, so it’s maybe too late for this use case.
Our first advice would be : Perform restoration tests regularly.
If you do so and encounter this error, you still have time to change your configuration and restore your previous backup key or generate a new one and get your news backups safe for the future.
A second advice would be to store the encryption key out of your PVE servers. No matter if it’s in Keepass, Bitwarden or any others vault software, the matter is : keep it safe in case of disaster recovyer.
As a last advice, we would say to include a copy of /etc/pve/storage.cfg file which includes your encryption key. Of course, don’t forget to encrypt this file in turn, to protect the encryption key it contains.
If you are a Cloud-pbs user or if you plan to, we encourage you to enable encryption as soon as possible, to increase your data security storage.
For our part, we use an offline digital safe for our systems.
On request, we can store your encryption key, to save you any future inconvenience (no obligation).
Take a look at our features, and contact us for more information about your Proxmox backup, management and security needs.
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