This problem occurred when I decided to move my server from VMWare ESX to XEN XCP. Completely disregarding any "How to move your WordPress site" articles, I foolishly decided that as long as I had a back up of my database and WordPress files, I should be ok. I'm not.
I used MySQLDump to back up my Multisite/Subdomain WordPress 3.2.1 site. Because I only had one server to work with, I couldn't leave the server up until I had the new one running, so I blanked it and installed XEN XCP 1.0 and then FreeBSD 8.2 for a server OS.
I rsync'd my WordPress files up to the proper Apache directory /usr/local/www/data/nelsonshack and then went about importing the database. There were no errors when doing so, so we were looking good.
However, now when I try to get to http://www.nelsonshack.com (my primary site) or even http://bloodytoe.nelsonshack.com (one of the subdomain blogs), I get this in the Safari browser: "Too many redirects occurred trying to open 'http://nelsonshack.com/wp-signup.php?new=nelsonshack.com'. This might occur if you open a page that is redirected to open another page which then is redirected to open the original page."
I have verified my FreeBSD/Apache/PERL/PHP/MySQL install by installing a brand new WordPress Multisite, just to make sure that we're good in that department. Once I did that, I refocused on my old database and files, trying to get them to work. This also gave me opportunity to create new .htaccess files and such. No good.
One possibility is that, because I migrated to a brand new server, I updated all of PHP/PERL/MySQL applications, so a different version of a MySQL setup might cause this (?).
I do have an xml backup of my main blog (bloodytoe.nelsonshack.com), so all is not lost. However, if anyone has something that I could try, that would be great.
--Update 2:07 PM MST: Renaming my .htaccess does not change anything.
--Update 2:11 PM MST: curl -v http://www.nelsonshack.com 2>&1 | grep Location: returns:
Location: http://nelsonshack.com/wp-signup.php?new=www (but so does a browser when trying to get to http://www.nelsonshack.com)