I am pulling my hair out trying to get this to build for 64 bit. I change it to x64 in the configuration settings, remove the WIN32 preprocessor directive and it still builds in 32 bit, and therefore doesn't run in latest Acrobat. Anyone had success with this?
I had success converting plug-ins to 64-bit, yes. I don't know what the WIN32 directive is that you removed, I didn't have to do that. You might have to change to x64 in multiple places in the VS settings. How are you making sure it is built in 32-bit? Are you looking in the right build folder?
I was trying all sorts of things and even removed the x86/WIN32 build. I got a message that only appears for a very short time that said it was invalid as 32 bit is no longer supprted and using the depency checker, all the DLLs were identified as x86. I ended up taking the piece I wanted and working it into my plugin, just adding source into a subfolder and doing a little initialization to get it stared and that works. Kind of a pain, but helpful in an odd way as I am able to move in known working chunks of code.
I took a look at a plugin project in Visual Studio 2019.
The plugins have a Platform choice of x64 and x86. That is all, no other settings seem to be relevant. They build to different folders as I have it set up. You need to make sure you do the same, because otherwise it will happily link both to the same place, leaving you with an unpredictable build. My output directory includes $(Platform)\$(Configuration) for ALL plaforms to make this work.