In Veeam Backup for Microsoft 365, a backup repository can be put into the Invalid state in any of the following cases:
- Local cache on an extended backup repository is different from that in object storage.
A cache state is verified by comparing timestamps and an identification number of the associated backup and proxy repositories; these values must be identical to each other.
- A repository lock in object storage is missing.
A repository lock is imposed by the backup proxy server and prevents such locked object storage from being added as an extension to any other backup repository configuration. A lock file is saved to the RepositoryLock directory. For more information, see Object Storage Structure.
- A trusted certificate for S3 Compatible object storage has been changed.
- If any of the following is true for extended backup repositories:
- A connection to object storage is missing.
- A container/bucket is missing or has been renamed.
- A repository folder is missing or has been renamed.
- A connection to DAS or NAS is missing.
Such an invalid backup repository becomes available after your DAS or NAS is online.
Once a repository is put into the Invalid state, restore or backup from/to such a repository is impossible.
Invalid backup repositories can be found in the Backup Infrastructure view under the Backup Repositories > Invalid node.
For more information on how to troubleshoot the Invalid state, see this Veeam KB article.