When installing Exchange Server 2010 on Windows Server 2008 R2 the Windows Firewall service must be enabled and the Windows Firewall must be running. If not, you will receive the following error and the installation of Exchange Server 2010 will fail.
Error:
The following error was generated when “$error.Clear(); Add-FirewallException -FirewallRule (New-Object Microsoft.Exchange.Security. WindowsFirewall.MSExchangeRPCByPortRule)” was run: “There are no more endpoints available from the endpoint mapper. (Exception from HRESULT: 0x800706D9)”.There are no more endpoints available from the endpoint mapper. (Exception from HRESULT: 0x800706D9)
Enabling and starting the Windows Firewall service will allow the installation to proceed and finish correctly.