I am currently trying to build a project for a 64 bit computer, but the configuration manager doesn't list 64 bit as an option. It gives me Win32, but no x64 (under "Platform"). I am using Visual Studio 2010 C++ Express.
It works on my other computer, but not this one. Most everything I have read has been saying to go up to the "Active Solution platform" drop down, and add 'x64' to it. I have tried that, but it still only lists Win32.
Select the Configuration Manager as given by the following picture.
The Select "New" from the menu as given by the following picture.
After that you will populate with following dialog box.
Once the process is completed, you will get the "x64" platform settings. Now you can select the Platform via Configuration Manager.