To rebuild all projects, you should clean the projects first, and then run a build.
         
         
         
         To clean and rebuild all projects:
            
         
         
         
         
            - From the main menu, select . The IDE shows the Clean dialog: 
               
               

               
               
             
            - Select the projects you want cleaned. 
 
            - Select the Start a build immediately box to enable the
                  option. 
 
            - Click OK.