Upgrade problems

I have been trying to upgrade my database for a while now. I deleted the previous wp and uploaded all files again repeatedly. However, every time I do so and go to upgrade.php, I get a blank page. The site is still up and I can login on the login page but any admin panel page redirects me to wp-admin/upgrade.php?_wp_http_referer=%2Fwp-admin%2F which is another blank page. Any suggestions? I also tried changing upgrade.php chod and cleared my cache/cookies. AAHH.