BizTalk 2010: Retrieving the COM class factory for component with CLSID {254B4003-2AA7-4C82-BB2E-18BA7F22DCD2} failed due to the following error: 80040154 Class not registered (Exception from HRESULT: 0x80040154 (REGDB_E_CLASSNOTREG)).

English: The send port could not activate the BizTalk HTTP services associated with the AS2 site’s application pool.

Better English: You are trying to run the 32-bit BTSHTTPReceive process with a 64-bit host.