Client Access Role fails during install

I have an existing windows 2003 exchange server in a windows 2003 AD. I have installed Server 2008 and am trying to install Exchange 2010.  The install runs up to the Client Access Role install fails then cancels the mail box and two other steps.

Error:

The fo;;owing error was generated when "$error.Clear{}:

new-autodiscoverVirtualDirectory -DomainController $RoledomainController-WSSecurityAuthentication:$True

"ws run: "An error occurred while creating the IIS virtual directory IIS://Poseidon.Marquisaurbach.com/W3SVC/1/Root?Autodiscover' on 'Poseidon'.",

An error occured while creating the IIS virtual directory 'IIS://Poseidon.MarquisAurbach.com /W3SVC/1/ROOT/Autodiscover' on 'Poseidon'.

Cannot create a file when that file already exists. Exception from [HRESULT:0x800700B7]

I've gone in and tried to remove all of the related IIS folders yet I still fail at this point.

What am I missing?

Thanks

Leon