Upgrade script error

I deleted my old files and uploaded my new ones per the instructions but when I try to run the upgrade script I get this error:

Not Acceptable
An appropriate representation of the requested resource /wp-admin/upgrade.php could not be found on this server.

Apache/1.3.37 Server at https://www.myblog.com Port 80

I can see all the files right there! What could be the problem? This is my first upgrade so bear with me here, thanks.