I am having the same issue.
The previous version of Streets and Trips that I have is the 2006, initially I chose to keep the old version while installing the trial of 2009 and it gave me the license initialization error near the end of the installation and when I tried to run the 2009, so I thought that 2009 is somehow conflicting with 2006 ... I uninstalled both of them, I did a reboot and reinstalled the trial of 2009, but that still did not help, and I still the the license initialization error.
Has anyone found a solution to this problem? I'm not sure what else to try.
From the review of ST 2009
it seems like there have been some great improvements done, but I'm a bit hesitant to buy a copy if I'm going to have this issue and I won't be able to use it.