Ok few things to try and a couple of questions
Question 1 - did it ever work ok for you and fully update and allow you to play the game? Or was this problem from day 1.
Question 2 - did you play the beta?
Question 3 - if it did work for you before - did you uninstall and reinstall the game?
Now first two things to try are:
1) Update to the latest .Net Framework (
http://www.microsoft.com/net/download)
2) Delete temporary updater files
-enable View Hidden files in the windows folder options
-navigate to C:\Users\Your USERNAME\AppData\Local\DoFUpdater\
-delete entire DoFUpdater folder
-when you run the game you`ll have to re-enter your CD key