I have a small WP multisite on Bluehost that was working very nicely running 3.5. I did all my backups this morning and upgraded to 3.5.1 using the WordPress install screen and not from the network dashboard - which I just found out is bad.
When I tried to access the dashboard my multisite had become a single site again. The upgrade had flagged that it was replacing my wp-config.php file and .htaccess files so I went back into them and added my additional code (let me know if you want to see it, it's pretty much boilerplate from the original 3.5 WPMU install).
Now when I try and log into the admin screen I get a Error 310 ERR_TOO_MANY_REDIRECTS and a 'This webpage has a redirect loop' error screen. I'm doing all this on Chrome.
I am willing to roll back to 3.5 but is there something I am missing aside from putting the multi-site mods in the wp-config.php and .htaccess file?