Hi Costas,
The error is saying you cannot mix 32 and 64 bit assembly together.
But i believe this is more of VS bug.
To correct this, take a screen shot of all the references you have.
Remove all the references ( including all the system references)
Clean your project.
If possible, target your .Net framework to 3.5.
If you have not set the platform 64 bit, set it now.
Re-add all the references.
When it comes to sapbouicom and sapbobscom, use the browse function to make sure it gets the 64bit com.
Rebuild your addon.
All other assembly needs to be in 64bit. Including B1wizardbase if you use it.
Sadly there is no 64bit b1wizardbase. You need to get the source code and recompile it.
Regards,
Edy