Some mac users have been experiencing problems with the USB stick that contains the European Geosciences Union General Assembly 2011 Programme.
If you have been affected, please take the USB to the EGU Information Desk (Ground Floor, Yellow Level, to the left once you get in the main entrance) and the problem can be resolved in 5-10 seconds. All student assistants have been instructed on how to resolve the issue.
This is a problem that has been an issue with some mac users, there are no reported issues with PC users.