MS VC++ 2012 is installed, development environment is fine tuned with all necessary libraries, QT and boost are no longer complaining about missing components etc… Then you find out that your application is not working in Windows XP. You see only a terse dialog with a message program.exe is not a valid Win32 application.

MS is slowly dropping XP support in all products. I can understand it. It is a 13 years old operating system. But the WXP market share is still around 25 % nowadays. If you need to cover most of your customers you can’t ignore that. Fortunately there is an easy solution. Add following to the linker options:

• for x86 console:
  /SUBSYSTEM:CONSOLE,5.01
• for x86 non-console:
  /SUBSYSTEM:WINDOWS,5.01

For x64 replace the 5.01 with 5.02. I recommend to stay with x86 only.