Admin user cannot see posts/threads

[enci]

I have an admin user that does not have permission to see posts or threads or forums. However, I am able to successfully login to the admin control panel. When I try to view a thread or post while logged into the user, I get this message:

Username you do not have permission to access this page. This could be due to one of several reasons:

Your user account may not have sufficient privileges to access this page. Are you trying to edit someone else's post, access administrative features or some other privileged system?
If you are trying to post, the administrator may have disabled your account, or it may be awaiting activation.

How do I resolve this issue? The user appears to have full admin access in the control panel.

This only seems to be affecting this one user. Other admin users are able to see the forums just fine.

Thanks.