I was doing some research on Hosting my WCF Service in IIS 6. My service supports both synchronous and asynchronous behavior (using msmq).
Below is a summary of hosting options based on operating system platform and communucation protocol:
Operating Platform Protocol Hosting OptionsWindows XP/SP2 HTTP IIS 5.1 or self-host Named Pipes, TCP, MSMQ Self-hostWindows Vista HTTP, Named Pipes, TCP, MSMQ WAS or self-hostWindows Server 2003 HTTP IIS 6.0 Named Pipes, TCP, MSMQ Self-hostWindows “Longhorn” Server HTTP, Named Pipes, TCP, MSMQ IIS 7.0/WAS or self-host
MSMQ, WCF and IIS 7
I found this article that contains very good information on getting MSMQ, WCF and IIS 7 (WAS) to play nice.