User cannot access redirected Documents folder, but can connect to share in Windows Explorer and access folder on server

Question

I am in the final stages of a cross-forest migration.  Users have Windows 7 workstations with redirected folders on a Windows Server 2012 box running in the old forest.  User accounts were not migrated.  The accounts in use have always
been in the "new" forest.  One of our challenges was the large volume of data in redirected folders.  I made sure users in the target forest had continued to have access to their redirected folders in the old forest and robocopied
the entire users share, copying the permissions with the files.  By doing incremental robocopies, we can get a final copy done now in about six hours.  The plan was simple: copy the files, do an incremental copy every night, on the night of the cutover
change the folder redirection policy Documents path from
\\oldserver\users\%USERNAME% to
\\newserver\users\%USERNAME%. The policy is configured to NOT copy user files from the existing folder to the new redirected folder.  Everything was going well until I tested the policy change.  After the folder redirection policy is updated
and applied, the user cannot access the private Documents folder.  For example, user Chester Tester logs on as ctester.  I open Windows Explorer and click the Documents shortcut.  I see one subfolder, which is subfolder of Public Documents. 
So I can look at Public Documents but when I click on the Documents folder (Under the Documents library link) I get an access denied error.  Now for the kicker, if I open another Windows Explorer window and edit the address bar to
\\newserver\users\ctester, I can navigate the Documents folder tree and see my thousands of documents. What the ....?
I'm hoping this is something really simple to fix!
TIA

Answer 1

HI Vivian,
Thank you for your reply.  Yes, the path in Group Policy Folder Redirection Root Path was updated to
\\NEWSERVER\users.  I had planned to point this to the distributed file system, so the first used was actually
\\domain\dfs\users.  To simplify things I have backed off to copying to just a normal share
\\newserver\users. 
We are using BASIC folder redirection and we create a folder for each user under the root path. 
We did not want the policy to move content, as we were seeing users requiring 15-20 minute logon times  (or higher) after the policy is changed.
Grant the User exclusive right to Documents - Disabled
Move the contents of Documents to the new location - Disabled
Related folder settings
Video - Follow Documents
Music - Follow Documents
Pictures - Follow Documents
Now when I change the folder redirection from old server to new server I now have TWO My Documents folders in the user's redirection folder on the server.  The redirected Documents points to an empty folder set.  The copied folders with all user
data are there, but folder redirection refuses to recognize the original folder.
I am looking at the full view of the folder, nothing hidden, so I'm wondering how a folder can have two subfolders with the exact same name.  For now, I just want the redirection to move from the old server to the new server properly.  I deleted
the new My Documents folder, rebooted the user's workstation and tried again.  The behavior repeats itself, i.e., a new My Documents folder is always created when the redirection policy is changed from the old server to the new server.  The environment
has about 1500 users with approximately 1.3TB of data in the redirected Documents folders.  OUCH!