I recently had to transfer my Maya 2011 license between two laptops and the LTU wouldn't launch. With a little research I found the solution*. If the LTU won't launch and you're left in the lurch without your software, you can delete the following files and relaunch Maya:
Win XP / 7
C:\ProgramData\FLEXnet\adskflex_*.data
Win XP C:\Documents and Settings\All Users\Application Data\FLEXnet\adskflex_*.data