I just recently installed lastpass on my windows 7 x64 box, the install was successful, and the plugin appears in all browsers, FF, IE, Chrome. However, in every browser, nothing happens after I tell last pass to save my password.
In FF, the window pops up asking me for a group, auto-login, etc.. I click the save, but nothing is ever added to my vault sites.
Same in Chrome, except that it runs in another browser tab, rather than in a pop-up window.