I wrote an asp.net web app which uses SMO against SQL Server 2008 to be able to run some DB scripts. It references these assemblies (in the C:\\Program Files\\Microsoft SQL
I resolve this only Just Right Click on Project navigate to Properties and Change Platform Target from 'Any' to 'x86'
You need to have the SMO components installed on your hosting provider as well. You can download them here.
I had SMO x64 installed, but SMO x86 was required on build server.