Yesterday my pc was freezing on boot up with an error message about Dr Watson failure to start, when dr watson deleted from task manager all worked fine. Subsequently I disabled Dr Watson. But now am getting an `Explorer.exe - Application Error' - error message in window reads `The instruction at'0x10017117' referenced memory at '0x00000000'. The memory could not be written. Click on OK to terminate the program.' When I do this computer seems to work fine. Anyone got any ideas what is causing this and how to stop it happening?