Grounded! ! ! Please help

Hello all,I am having a problem which I cannot seem to figure out.Just recently I am experiencing a MSFS crash after I selecta saved flight and hit the "fly now" button.The screen goes black and then an error message comes up.The message is: The instruction at "0x016214ca" referencedmemory at "0x016214ca" The memory could not be written"This has just come up recently and I have not downloaded anyscenery that could affect it. It comes up on every saved flight.Any help would be very much appreciated.Thanks,john