I reported this quite some time ago but it's still the same.
When I click on Undercroft in my bookmarked list it takes me to the site where the screen says:
"Page could not be found"
I am signed in however and any personal notifications still appear in red on the tab on the top right. I have to click "Home" and then it signs me in OK.
So it appears to be a little glitch.
I have tried IE and Firefox. I've also updated my bookmark.