Folder redirection: why domain administrator can’t access folder?

I setup-ped folder redirection in a windows server 2008 environment.
The problem is that Domain Admins can’t access ‘My Documents’ user folder, so i can’t also backup folder.
How is possible ?
Is it correct ?
How to do to correctly setup folder redirection allowing user admin access ?

Thanks

Don’t enable the option that grants the user exclusive rights to the folder. We don’t enable this on ANY of the redirects (that includes application data – makes it much easier to do stuff like generating signatures).

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