Simplify settings related to bitness
The bitness related settings are scattered all over and overcomplicate the development process.
They shoul all just use whatever is selected Configuration Manager / Active Solution Platform or use one central setting.
Menut / Tools / Options / Web Projects:
Use the 64 bit version of IIS Express for websites and projects
Project Properties / Web:
Menu: Test / Test Settings / Default Processor Architecture / x64 | x32