My Site as separate web application
During the configuration of the SharePoint site, per Scot Hillier's book you are instructed to set up the Shared Services Provider creating separate Web Applications for the Shared Services (on port 8080) and Personal sites (on port 8081). Once I did this I continued on until I got to the Shared Services section of the book (chapter 4) and began playing with the My Site feature. The first thing I noticed (after enabling Self Service Site creation) was that each My Site I tried to create (as various different users) would fail. I began digging through the Central Admin and went to the Shared Services administration. On the 'User Profile and My Sites' section, click the 'My Site Settings' link and ensure that in the 'Personal Site Services' section the 'Personal Site Provider' is your Web Application you indicated as your Personal Sites Application (if you followed the book's instructions in setting up Shared Services it should be the app on p...