One of our engineers has a problem trying to use Copy Tree.  He always gets the error that says it could not copy the file because it could not create the folder in the local cache.  It then suggests that the name may contain invalid characters.  It does not matter which file(s) he selects or which folders they are in.  His user, as well as all other engineer users, does not exclude any folders or have anything different in the variable settings.

It appears that this has always been this way since he started a couple years ago and after it fails he gets another engineer to create it for him.  This time he asked me to help and it worked fine for me but not for him.