I have just recently migrated a couple of sites to a new VPS hosting package.
Since moving them I can no longer access the login page using the adminbar login link - it return a 404 for one site it just automatically redirects to the home page for the other.
I can go directly to the login.php page and login.
After I have logged in I also have the same issue with the logout link on the adminbar.
Has anyone come across this before - it's very frustrating.