Solved! Go to Solution.
It sounds like you're using a bad path to your DLL or forgot to include it in the "always include" in the build.
Two quick questions:
1) is this on the same PC as the dev system? This is asked to understand if everything works on one PC or if the deployment is where things break. It'll help narrow down whether it's failing to install required things on one PC or if it's likely to be a pathing issue.
2) Your post mentions .NET. Have you added your DLLs to the Global Assembly Cache following MS's best practices? If not, try this step first and see if the error goes away.
finallly I got the solution, I copied all the .dll in the build folder manually and .exe works fine. I didnt know why these dll are not included automatically while building the exe though all the dll are there in the project.