cant get SQL server to connect to SSMA

yea the guy that programmed the database and the sole developer for the company died a few years ago and I got tapped to fill his position but I only ever learned access for databases and it is no longer sufficient for the growing company so now I get to learn on the fly how to take a base level access database and turn it into a corporate level database with low level security, admin interface, and user log in and tracking, fortunately I am familiar with .Net but this transfer is just frustrating me, I guess all I can say is I have SSMA SSMS and the server configuration manager installed the SSMS seem fine I haven’t had to trouble shoot anything there yet and the command prompt checks come back clean, I have imported the access database into SSMA and am trying to connect it to the localhost\SQLEXPRESS server but when the window opens I have tried both the windows authentication and SQL authentication in the basic tab and the connect button stays greyed out…the AI says it’s because the configuration manager cant connect due that .mof file being missing it was apparently supposed to be a part of SQL Express but like I said, I downloaded it twice and still can’t get the file