Fail to install Javaserver Faces 1.1

I just install Designer 7.1. When I create a Composite App. project, I got error for fail to install javaserver faces 1.1. This happened only one of the PC. Any idea what’s causes it and how to fix it.
Thanks for any help.

JSF plugin should come along with Designer 7.1. But you still can download and install it by yourself via HELP ->SOFTWARE UPDATES->UPDATES & INSTALL…