Warning about two accounts when syncing
dstillman
Zotero Team
This discussion was created from comments split from: Question on 'conflict resolution'.
Upgrade Storage
This isn't a "conflict resolution" message — that's something completely different.
You get this message when you've previously synced with one Zotero account on a given computer and then try to sync with another. Zotero warns you that it will need to delete all local data for the old account, requires you to check a checkbox saying "Remove all data for “[old account]” from this computer", and says to make sure you either have uploaded any data to the old account before continuing or have a backup of your Zotero data directory.
Assuming one of those is the case, you can restore by either switching back to the old account or restoring from the backup.
The local zotero.sqlite files aren't relevant, because when you switch accounts it deletes all the local data, as the message says and as you give it explicit permission to do.
In no way does this affect an online library, so you're mistaken there. You're likely just looking in the new account online rather than the old one.