What Am I Missing With Multisite

Good evening all. I took the advice of ‘kmessinger’ in an earlier post and atempted the multisite install again for my multiple blogs. Fortunately, I found a plug-in that does the main functions for you this go round. Anyway, the multisite enablling went well and all seems fine on that end. However, I seem to be missing soemthing somewhere. I added a new site and got the theme to work. What I am having trouble with is when I click on ‘My Sites’ in the Admin Bar and try to access any of the functions under it, i get a 404 Page Not Found Error. This happens whether it’s the dashboard, adding a new post or managing comments. On the other hand, I am able to view the page. It just appears that all the admin functions will not work on the additional site. I had to set multisite network up under subdirectories as my host doesn’t appear to support subdomains. Can any one help me figure out where I went wrong? Also, why are my posts from my main site showing up?