VSTA cannot open dll

Hi friends

I have a vsta application developed and run at SW 2011. When I installed the SW 2012, I recompiled it to 2012, but the application doesn´t work at SW 2011 anymore. The problem about "cannot open dll" it´s very common for SolidWorks. Does anybody have an idea how to solve this problem? I tryied change the reference dll from 2012 to 2011 but without solutions. I think the problems is about SW dll versions or the VSTA dll, but not sure.

SolidworksApi macros