This message can be displayed during installation. Installation can fail because of the incorrect instantiation of many things, including the license file.

The license key could have been corrupted when you attempted to install, remove, or relocate files. Problems can arise when installing Maple on a secondary hard drive: formatting the primary hard drive that contains the operating system will cause the registry to be cleaned and therefore the license file will be removed.  Also, it is possible that a virus damaged the license file.  

Solution:

Try to restart Maple.

If this does not work, try reinstalling Maple but shut down all copies of Maple before attempting the reinstallation.

Maplesoft Web Store, Technical Support