I've had problems with several sites when using Firefox 3 (the same sites work fine with Safari), so in order to check if it was the browser itself or its associated setup files I quit Firefox, then renamed the Firefox folder (~USERNAME/LibraryApplication Support/Firefox) to something else ("Firefox OLD"), and restarted Firefox (forcing Firefox to create a fresh "Firefox" folder with new setup files etc.). It turns out that Firefox now could enter those problematic sites without any issues, ergo the "Firefox" folder was the culprit. However, I have plenty of bookmarks in that old Firefox folder and assumed that I just had to copy over the "bookmarks.html" file as with older Firefox versions, but that turns out not to be the case. A Google search quickly told me that there's a completely different and more complicated way to do things now, with symbolic links and whatever which leaves me scratching my head. I am of course wondering how to transfer all my old Firefox 3 bookmarks into the newly created "Firefox" folder? I guess the same goes for my saved passwords, cookies and so on as well.