I followed WordPress instructions for upgrading to 2.7, and thought I had backed up the appropriate files. The "complete upgrade" page is blank. Attempting to go to dashboard nets a error page ("index.html missing); my user name is no longer recognized (had to create a new one to get to the forum, since "retrieve password" didn't work either). Tried a reinstall through Powweb (my provider) but still can't access the final steps. Have uploaded my old wp-config.php, reset cookies, restarted browser, all to no avail. Do I have to start over from scratch?