[dba-SQLServer] Access Denied when trying to attach a database

I think I've asked this before, but if so I've forgotten the answer. I'm
trying to attach a sample database from the book "SQL Server 2008 MDX Step
by Step", and I'm getting this error.

Anybody know the way around this problem?

TIA,

-- 
Arthur
Cell: 647.710.1314

Prediction is difficult, especially of the future.
  -- Niels Bohr