Are you using CCS 5.4? If so, you might be running into a known bug as described in this post.
In that case, I would recommend updating to CCS 5.5 which fixes this issue. Rather than updating your existing version, a full complete installation of 5.5 is recommended. You can download and install CCS 5.5 from http://processors.wiki.ti.com/index.php/Download_CCS