I was playing around with MySite and imported a data view web part using a .dwp file. After refreshing the page, I got a nasty error. The error stated that the web part referenced a list that does not exist. From that moment on, I could not navigate to the http://…./MySite/default.aspx because it always gave me the same error.

How can you solve this? Just open the page like this: http://…./MySite/default.aspx?contents=1. You then get this (click the thumbnail):

From that page you can delete the offending web part.