"You’ve used a newer version of 1Password on this device"

I just ran into this as well. I switched to the beta channel a couple of months ago to get a bug fix, then switched my setting back to stable a few weeks ago, expecting that I'd still be getting betas for a while until the relevant stable version came out. I've received a few beta updates since then.

This morning, I had the notice in 1P that it wanted to restart after an update, so I did that. Upon restart, it was on a newer beta version and had another restart message. I hit the button again, and this time, I got the message above about having used a newer version. So 1P must have switched to a stable version that's behind the beta version. Again, this is all driven by the built-in update mechanism; I did no manual updates/installs using versions off the web site.

I think the version I started on today was 8.10.1 beta per the about box, and Finder now shows I'm on version 8.10.3 after the two restarts.

I'll go through the process to nuke things and get operational again, but as a suggestion, it'd be great to have a built-in way to handle this. Two ideas:

1. Isn't simply switching to the latest beta always a way back to a working app? If so, consider adding a button to the dialog to do just that, without making the user do the job of finding, downloading, and installing the beta.

2. Add functionality to check for a keyboard modifier (e.g., probably shift or option) during startup and offer to reset the database. Basically, an automation of the manual procedure. You could add another button to the dialog as an alternate route to the feature in case people forget it's there. Note that this feature is useful to any user beyond this situation.