Can't sign-in to Messages app on iMac. Get "an unknown error occurred". Just updated to Tahoe 26.6.2
iMac 24″, macOS 26.6
Irene Prat wrote:
Can't sign-in to Messages app on iMac. Get "an unknown error occurred". Just updated to Tahoe 26.6.2
ref: If you can’t turn on or sign in to iMessage or FaceTime on Mac - Apple Support
If you can't turn on or sign in to iMessage or FaceTime...
Unknown errors normally require a shotgun approach (try everything that might help) to solve. If you leave additional replies here, I may be able to help. My first shotgun suggestion: Be certain you have a current backup of your Mac. Use Time Machine or another trusted Mac backup utility to create that backup. Then boot into recovery mode, and run Repair on your data volume using Disk Utility, available in recovery mode. Then try Messages again. If you need information on any part of my suggestion, I'll try to reply with additional details.
How to fix "unknown error" at sign in
