The Sitecore XP 8.0 Initial Release update package doesn't add some necessary security roles. As a result, some functionality doesn't work as expected for Sitecore Client users.
For example, this issue may prevent Email Experience Manager from loading properly.
The following roles are missing:
    - sitecore\Analytics Advanced Testing
 
    - sitecore\Analytics Management Reporting
 
    - sitecore\Experience Explorer
 
    - sitecore\Facebook Message Reviewer
 
    - sitecore\List Manager Editors
 
    - sitecore\Social Marketer Message Reviewer
 
    - sitecore\Social Message Author
 
    - sitecore\Social Message Workflow Editor
 
    - sitecore\Social Message Workflow Reviewer
 
    - sitecore\Twitter Message Reviewer
 
    - sitecore\Sitecore Client Social Authoring
 
To resolve the described issue, install the following patch via the Installation Wizard application:
Sitecore.Support.121139