VFP class license error

I have the occasional problem when I try to debug third party plugins sometimes I get OLE error code 0x80040112 class is not licensed for use and sometimes I get you have 14 day left for this demo license what is the cause of this and how can I add break points in these plugins to find the fault.as I am able to rebuild the app and also able to make changes to the main program and build the EXE I am not sure what is causing the problem I have looked on microsoft site but the answers appear to relate to built in VFP classes

You need to add class license in the TOOLS>OPTIONS>CONTROLS that will help with the class not licensed error check out this article http://support.microsoft.com/kb/139154 may have additional help ?