RoboCopy Error 5 Access Denied

If you recieve a Access denied message from robocopy (Error 5)
Then remember to check the permissions of the target as well as the source directories.
Especially if you have already copied the area before and permissions have changed since when you first setup the target directory.

In some cases it may be required to add COPY:DT to override the default COPY:DAT which copies file attributes. Modifying these attributes sometime generates the error 5.