Visual Studio Save – Microsoft Q&A

Have A C++ program in Visual Studio, making changes and when finish, issue a “save all” command which should save all of the changes, I would think. I then issue a “re build” and issue the “save all” command again. However, after execution and exiting the Visual Studio program, I would think all would be saved. However, when I access the Visual Studio program and open my project, all of the changes are gone?? Not sure what is going on but tried several different times with the same results. Am I using the wrong command when I say “save all” or? please let me know, Sid Kraft