1.From the Main Menu, Click on the “Tools” then “Option”
2.“Option” Window will appear,
3.Click on the Plus Sign (+) on the Left side of "Debugging" (Found on the Left Side Panel)
4.Select on the “Edit and Continue”
5.Check on the “Enable Edit and Continue” then Click on “Ok” Button
6.On the “Solution Explore”, Double Click on the “My Project” Icon
Alternative:
Or you may right click on the Project Name then Select Properties
7.“Application Property Window” will be displayed
8.On the “Compile” Tab, Click on the “Advanced Compile Options...”
9.“Advance Compiler Settings” Window will appear, 10.then UnCheck the “Enable Optimizations”, and Click on “Ok” Button.
I hope this helps... Good luck!
mj_octaviojr@yahoo.com 
