I am trying to restore my catalogs after a clean new installation of WIN10 64bit 1909. I have a full backup and after that 3 successive incremental backups. Restore of the full backup worked fine, but the restore of the first incremental backup failed: Backup controls were set according to picture "restore1", when starting the backup I get the popup as shown in picture "restore2". I don't understand that at all. What is meant with data from 2 backup sessions? Why is there a reference to CDs/DVDs - all my backups are on hard disks.
I once clicked ok on that popup, then I was asked for the restored catalogue, to which the data should be added, then the restoer process took place, a blue progress bar was shown, and then another popup asked for the second backup session data - at which I was at a complete loss and canceled the process.
Restoring from incremental backups has always been a big issue in all Organizer versions. Now, when you type 'restore from incremental backup' in the search box of the home page, you get two different docs, one for for PSE2018 the other for PSE2015 and older. None of them explain the process in detail, and I don't know if there has been a difference in those versions. You are supposed to follow the on-screen process which is not what you may expect.
I have always advocated against using incremental backups unless you understand the process and you have tested it successfully. It does not save you a lot of backup time relative to a full backup either.
To be short, what is counter-intuitive is that you are expected to follow the instructions which ask you to point to the last incremental version before the older ones.
Since I have always been unable to find a detailed Adobe doc about the process, I'll take the risk to explain how I understand it (please correct me if I am wrong).
What's totally unusual in the backup process of the organizer is that you backup at the same time a catalog and a library of media files.
You can verify that in the case of incremental backups, the structure of the resulting backup folder is exactly the same in each version.
The catalog backup of the catalog folder always includes the full current backup. The catalog copy in the last incremental backup is exactly what will be restored.
The media files included in each incremental backup appear to be all new or changed files relative to the immediately previous version.
What about deleted media files? There is no longer any link for them in the final backup of the catalog folder.
So, you can imagine that after the catalog database is restored, the process starts with restoring the media files copied in the last incremental backup, and flag them as 'already restored'. Then it looks at the media files in the previous incremental backup, restores them and flag them. And so on until the original full backup is accessed. All files in the final catalog will be restored if they have not already been flagged before. Everything is restored without having to restore deleted files.
The good thing in the workflow is that if you want to restore, from instance the 3rd incremental backup instead of the 5th (the last one), you simply start the restore with the 3rd incremental backup, ignoring the more recent one.