Can't access files on external drive after reformatting Macbook Pro

Question

I recently had to reformat my Macbook Pro, and imported my account and settings from Time Machine via the Migration Assistant. Everything on the Mac itself is fine, but now I don't have permission to access almost everything on my external drive. A number of folders have the little red 'no access' sign on them and I can't rename or move anything. Looking at the info for these files, it appears that access rights were attached only to my old user account. Is there some way to reassign these files and folders to my new user account? Thanks.

Answer 1

1. Open the Get Info dialog of the affected files and folders.
2. At the bottom, you can assign permissions. If this is disabled, click the lock icon and authenticate.
3. Then, add your account to the list, and select Read & Write privilege.
4. Open the cogwheel menu and select Make username (me) the owner.
5. Remove your old user account from the list (the other element with a "single person" icon).
6. Then open the cogwheel menu again and select Apply to enclosed items....

Answer 2

if you imported from migration assistant, did you create a new account after reformatting? or did you restore the backup from Time Machine during the initial setup assistant?

You may have created a second user upon migration. Check in you System Preferences->Accounts to see if there are multiple users present. If so, the user you imported probably has permission to access your external drive.

The other thing to try is ignore ownership. Select your external drive, go to File->Get Info. There is a checkbox at the bottom for "Ignore ownership on this volume." If it's greyed out, click the lock and authenticate. Then check the box. I prefer this method since it doesn't actually change the file permissions, just makes the OS ignore them.