When troubleshooting installation problems, keep these things in mind:
*Read the ReadMe.txt file included in the installation files and make sure you’ve followed each step correctly.
*Check your wp-config.php file to make sure that database information is correct.
*Check the closed tickets at the WordPress MU Tracking site at http://trac.mu.wordpress.org/report/6 You might find that comeone else experienced the same issue your’re having – along with a colution to the problem.
*Visit the WordPress MU support Forum at http://mu.wordpress.org and search though the messages there to see if anyone else has experienced an issue to the one you’re experiencing right now. This is a great place to reference and problem solve.
*If you’re unable to solve your problem with the preceding methods, you can submit a bug report to the WordPress MU Bug Tracking site. Make sure you include the following information in your bug report:
Is your virtual host (vhost) true or false?
What is the path to your WordPress MU installation? (did you install it in the root directory of your Web server or in its own folder?)
Is there anything in yoru error logs? Make a copy of the complete text of any message(s) that shows in your error logs. Include this text when requesting support.
Is the database information in your wp-config.php file correct?
Please make sure you mention the version number you’re using of WordPress.
If you don’t include the basic information in your bug report, don’t be sureprised if you’re redirected to this page: http://trac.mu.wordpress.org/wiki/DebugginWpmu This isn’t meant to be unhelpful. The moderators of the list do want to help you; however, they need some specific information your setup so that they can help you help yourself.

