Problems with Visual Studio .NET

I have been working on a project for about a month now, and every day I have loaded my project and no problems, today I load it and it has rolled back to the original settings with the original files, in Visual Studio 6 format, I am confused, why has this happened?? Additionally how come when I click on the project and click save all the C and header files save but the project itself doesn''t update with new files e.t.c and stays as the original settings?? I am incredibly confused and this is causing me a real problem as I have to now add all my files again and the command line stuff for the compiler. WDA