Over the weekend, AgileBits wrote a blog post saying that 1Password users were getting an error message when trying to start the app. This error is due to the expiration of the developer certificate this past Saturday. The company knew the certificate was expiring but didn’t realize it would cause an issue with the software.
First, it should be noted that this only affects people who have downloaded 1Password directly from the AgileBits website. If you use the version from the Mac App Store, this error shouldn’t be a problem for you.
This error is because of a change in how macOS Sierra handles developer certificates. In previous versions, the expiration of a code signing certificate didn’t have an impact on software that was already shipped. But in Sierra, Apple requires apps to have a provisioning profile.
This profile tells macOS that the app has been checked by Apple against an online database and it’s allowed to perform system actions, called entitlements. But the profile is signed with the certificate, so when the certificate expires, the provisioning profile becomes invalid.
AgileBits has already fixed the issue on its end, so all you have to do is download the updated version of 1Password, version 6.5.5. Again, if you’ve been using 1Password from the Mac App Store, you don’t need to worry. The company provided a video to show you how to do it, as seen below: