macOS 15.3 Patches Critical Backup Bugs Affecting Multiple Applications

macOS 15.3 Fixes Backup Bugs Affecting Multiple Apps

macOS 15.2 Sequoia introduced one or more backup bugs that affected Apple's Time Machine utility and third-party apps like SuperDuper and CarbonCopyCloner. The primary issue was a Resource Busy error occurring during the replication of the Data volume, particularly when copying Preboot or Recovery files. This bug prevented bootable backups from being created successfully.

SuperDuper developer Dave Nanian reported that Apple had fixed the problem in macOS 15.3. Synology also confirmed the same issue was affecting bootable backups to its NAS systems.

The impact extended beyond just bootable backups, with users reporting failures in non-bootable Time Machine backups as well. The issue appeared to be specific to Apple Silicon Macs.

Apple has not yet commented on the issue.