We finally have a preview of the Apple Intelligence features with iOS 18.1 and macOS 15.1 beta, which were released to developers yesterday. As we dig into what’s new in the betas, some Mac users have noticed that it may not be possible to use Apple Intelligence when macOS beta is installed on an external drive.
No AI when running macOS 15.1 beta on an external drive
According to reports, users who tried to enable Apple Intelligence on a macOS installation running on an external drive were unable to experience the feature. Although the option to enable Apple Intelligence is there, the system fails to finish downloading and installing the required language models.
9to5Mac then found an alert message in the beta version of Xcode that explicitly says that the Code Prediction feature “is not available when booting from an external disk.” Based on system logs seen by 9to5Mac, it seems that this restriction applies to all Apple Intelligence…
Source 9to5mac.com