Report Manager Blank Page

By right, we should be able to see the 2 tabs in report manager homepage, Contents and Properties. BUT now its missing.
Confirm that site already added into trusted site.

Double check on:

1. Browse to the report manager virtual directory, open the web.config. (Make sure it has the <identity impersonate="true"/>)
2. Uncheck the enable anonymous access in the directory security in IIS.
3. Log in locally on your report server computer as a member of the Local Administrators group

My situation is missing the impersonate in web.config
Hope this can help. :)