I often get an "error" message when I click on my Preferredguest.com bookmark.
When that happens, I just click on my Starwood.com bookmark . Once the Starwood home page comes up, I click on the "Starwood Preferred Guest" link on the bottom left. 9 times out of 10 it brings me directly to my Preferredguest page, with my balance, et al.
Aloha