The IIS Web Site "|0" has already been extended. The registry key "HKLM\Software\Microsoft\Shared Tools\Web Server Extensions\Ports\Port ...

The IIS Web Site "|0" has already been extended. The registry key "HKLM\Software\Microsoft\Shared Tools\Web Server Extensions\Ports\Port /LM/W3SVC/|1:" and file "|2\_vti_pvt\service.cnf" indicate that the IIS Web Site has been extended. If you are sure the IIS Web Site has not been extended with Microsoft SharePoint Foundation, delete the registry key and file, and then try extending the IIS Web Site again.