I work on an x86 pc and use .NET4.0 (same probelem with 3.5) in VS2010. When I make a new Project (e.g. WinFormsApp), the first thing I want to do is to change the target platform of the project/solution to "Any CPU".
I do the following:
Project Properties -> build -> change TargetPlatform to "Any CPU"
On top of the properties page the platform is still "Active (x86)", so I do
Solution Properties -> ConfigurationsMgr -> Platform -> new (since nothing but x86 is available) and create the solution platform "Any CPU".
Now the project properties are "Active (Any CPU)" and I can change it back and forth as I like.
And now the Problem: When I add a new Project, it is again set to "Active (x86)" and I -again - can't change the project settings. In the SolutionProperties -> ConfigurationManager for this second project, the "Any CPU" platform is not available and I can't add a new one, since it tells me that a solution platform for AnyCPU is already there...
What am I doing wrong? Can it be so hard to set a newly created project to AnyCPU?
In the configuration Manager, you can add a new platform for your project. However, you need to uncheck the "Create new solution platforms" if you already added the platform for your solution, otherwise you will indeed get the warning that the solution platform is already there.