Every time you launch an Enfocus product, you will have to enter the Product Key. It will say that your trial has expired and you have to register the product.
This is probably related to not having enough permissions
Vista (and above) specific
If you are an administrator then you should start Acrobat with the option, Run as Administrator, you can do that by right clicking on Acrobat and choosing that option. After do the registration.
- Please check the permissions on the following folder, they should be read and write for everybody:
Mac => HD:Library:Preferences:Enfocus Prefs Folder
Windows XP => C:/Documents & Settings/All users/Application data/Enfocus Prefs Folder
Windows Vista => C:/ProgramData/Enfocus Prefs Folder