How to Troubleshoot: MacOS error – Could not sign in to iMessage
Several users have reported that they cannot log into iMessage using their Apple ID. Users receive the following message:
“Could not sign in to iMessage. An error occurred during activation. Please try again.”
This is an important issue. This problem seems to only affect Mac users. If you encounter this problem, iMessage will not work until you resolve the issue.
Try the following troubleshooting steps. After each step, try logging back into iMessage to see if the problem is resolved.