Below error encounter while moving application from 32 bit OS to 64 bit OS.
Class not registered (Exception from HRESULT: 0x80040154 (REGDB_E_CLASSNOTREG))”.
Change project target platform to *86
After changed platform target build and deploy it. If it is wcf service after published to IIS you will get a following error on 64 bit OS
If you are hosting any wcf service the apppool which reference the service should run under 32 bit