When C++ links your programs, it goes through and examines what it has already linked, from previous times you have linked.
An incremential link will actually be slightly faster than a full link as it goes through and will only link what has changed since last time. The message you are getting is telling you that the data that VS keeps regarding its linker is invalid, so it cannot do the link incrementially, and thus is performing a full-link.
That message isnt actually a bug or a glitch or anything to worry about and its not affecting your program at all, its just one of the nuances of Visual C++ that you will learn to recognize after using the environment for awhile.
If it ain't broke.... DONT FIX IT !!!