WordPress MU

I face such a problem while I install Wordpress Mu.

WordPress database error: [Duplicate entry '1' for key 1]
INSERT INTO wp_sitecategories VALUES (1, 'Uncategorized', 'uncategorized', NOW())

WordPress database error: [Duplicate entry '2' for key 1]
INSERT INTO wp_sitecategories VALUES (2, 'Blogroll', 'blogroll', NOW())

how should I do?
Please help me, thanks!

you clicked to install twice, that's simple... you have to drop all the existing content of your database to install it once... but wait for the end of the process....

thanks so much!