Q: regarding 'permission':

I am the owner, using OS X 10.7. and the only one using my Mac Book Pro.

I have a problem with permissions.

On this site, I read as a solution 

Select the external drive's icon in the Finder and open the Get Info dialog. There's a check box labeled "Ignore permissions on this device." Is it checked? If so, uncheck it "

There is no such check box in my Get Info box.

Why and What can I do about this?

I WOULD APPRECIATE ANY HELP.

THANKS!

Erseii