Move to a New Mac Without Losing Track of User Accounts
Migration Assistant can move documents, applications, user accounts and settings between Macs. The easily missed decision is which account will contain your work afterwards, especially if you have already started using the replacement computer.
Inventory both computers
Back up the old Mac and protect any new files already created on the replacement. Make a short acceptance list: a recent work document, the main photo library, a browser bookmark folder and any specialist application data. Include every person who uses the old computer.
Check that the destination has room for the selected information. Keep both computers powered and choose a time when neither is needed for an urgent task. Migration may take hours; a long transfer is not a suitable experiment immediately before a meeting.
Read the account-name decision
On the new Mac, Migration Assistant offers transfer from a Mac, Time Machine backup or startup disk. On the old Mac, choose transfer to another Mac. Compare the security code if one appears, then inspect the categories available for transfer.
If an account name already exists on the new Mac, Apple describes options to replace that account or rename the transferred account so both remain. Do not casually replace an account containing new work. Decide which identity you intend to use daily and keep an independent copy before accepting a replacement.
After migration, log in to the transferred account and work through your acceptance list. A file may exist under a different user's home folder even when your current Desktop looks empty. Open important apps and check whether they need compatible versions, licence activation or account sign-in. Email may require authentication again.
The old Mac's information is not deleted by Migration Assistant. Keep it intact until the new workflow and a new backup have been verified.
Source: Apple's Mac-to-Mac migration guide.
For help with your Mac, contact AEPC in East Auckland or call 027 908 8880 to discuss your requirements.