If you use the default project (go to File/Project/Close and it should re-open the default project), and open a simple sample program, can you compile that?
If you're opening an existing project, did you follow these directions from the top of the Release Notes:
Reminder: When opening a project in a new version of Dynamic C, update the "Include Path" tab in the Project Options to use the new Dynamic C directory. (Or change it to ".\include" to always use the current compiler's include directory.)
If your project has a custom LIB.DIR file, make sure your LIB.DIR points to the libraries from the Dynamic C 10.72C installation.
Those steps will hopefully help you narrow down the cause. Please post if you find a solution so it can help others who might search and find your forum question.