Hi all
Is it in some way possible to restore from a backup to Dropbox without the matching/corresponding sync key (either QR code or words list) or, due to encryption, will I need to start all over again?
Sue
Hi Sue,
Thank you for using Codebook and posting to the discussion forum.
Your Sync Key is used to encrypt all your synced Codebook data, so it’s necessary to have a matching Sync Key if you’re attempting to restore from Dropbox.
There are complete instructions here for restoring from a backup with your Sync Key: Codebook Help - Restore Data from Backup Also on that page is a link to iCloud or iTunes restore if you’re using an iOS device and have an iTunes or iCloud backup of your device that’s another potential option for restoring.
There are two different option for backing up your Sync Key within Codebook: printing out a Sync Key QR Code or writing down a Sync Key Word List. When you first setup your Sync Key within Codebook, you should be prompted to take a backup, do you happen to recall if you took a backup of your Sync Key? There’s more information on this page about Sync Key Backup: Codebook Help - Backup Your Sync Key
Do you have Codebook on another device by any chance? If you do, and you’ve been syncing that other device with the same Dropbox, then it will also have a copy of your Codebook Sync Key which you could use to restore.
Finally, one last thing that would be worth checking: Open Dropbox in a web browser and see if you have a copy of strip.db file (potentially in the Zetetic folder or in the trash). This would be a copy of your legacy Codebook database from before the Sync Key encrypted with your Codebook Master Password, so it might allow you to recover some (old) data if it’s present in Dropbox.
If you do end up needing to start over because none of these options or possible, we’d highly recommend taking a backup of your Sync Key after creating it.
Please let me know if this information is helpful and if there’s anything else I can do to assist. Thanks!
Thanks for your extensive reply mmoore, greatly appreciated.
Unfortunately it looks like I’m going to have to start all over again as none of your suggestions fit my circumstance, but it was worth a try in asking.
Sue 
does this mean the synched data is encrypted twice? Once with your DB password and then again with the synch key?
Or are the changes in your DB first unencrypted (read from the DB) and then encrypted with the sync key, and then synced to the cloud service?
Why not use the same DB password for both?
I have been trying to find an answer but I can’t so sorry if this is explained somewhere.
Sorry to hear that none of the restoration options were available for you.
Your Codebook database is encrypted locally (on device) using your Codebook Master Password as key material. When syncing, Codebook encrypts “chunks of changes” (codebook-changeset-[number].db files in your cloud service) with your Sync Key. So to answer your question directly – no. Synced data is encrypted once with the Sync Key.
I believe this post by my colleague helps explain why we made the decision to use a Sync Key to encrypt synced data: Why Does Codebook Require a Sync Key?
Let me know if that answers your questions and if you have any further questions. Thanks!
Yes clear, thank you!