how to clear all acl permissions

Reset User Permissions and ACLs in Lion/Mountain Lion

Boot to the Recovery HD:

Restart the computer and after the chime press and hold down the COMMAND and R keys until the menu screen appears. Alternatively, restart the computer and after the chime press and hold down the OPTION key until the boot manager screen appears. Select the Recovery HD and click on the downward pointing arrow button.

From the Utilities menu select Terminal. At the Terminal prompt enter: resetpassword. Press RETURN. When the window opens select your startup drive where it says "Select the volume containing the user account:" At the bottom of the window you will see, "Reset Home folder permissions and ACLs." Click on the Reset button.

As far as I am aware, Kappy's suggestion would only reset the permissions on home folders in /Users on the boto drive. It would not reset permissions for an entire drive.

The following will I believe do what you want but be very, very careful with this command. You should definitately not do it on your entire boot drive. You could do it on a folder on your boot drive, or you can (if your happy) do it on an entire additional volume.

The -R flag means do recursively, the -N flag means remove ACLs

cd /Volumes

sudo chmod -R -N nameofvolumetoremoveallACLsfrom

e.g.

cd /Volumes

sudo chmod -R -N ExternalDrive

If you want to reset a single file/folder then

sudo chmod -N /path/to/folder/or/file

If you want to reset a folder and everything in it

sudo chmod -R -N /path/to/folder

Do not unless you want to destroy your system do

sudo chmod -R -N /

If you want to do it without altering a password the command is

chmod -R -N <path-to-root-directory>

You need root privs, so for you the command is probably

sudo chmod -N <path-to-root-directory>

You are correct. I would assume that repairing permissions with Disk Utility should take care of all else. DU does not check or repair permissions in the Home folder. 🙂