The IWamAdmin::AppRecover method reinstates a Web application definition that was previously deleted with the IWamAdmin::AppDeleteRecoverable method. If the application specified was not previously deleted, it will be reregistered with MTS.
HRESULT STDMETHODCALLTYPE AppRecover( 
  LPCWSTR szMDPath,  // [string][unique][in] 
  BOOL fRecursive    // [in] 
); 
 The method will return NO_ERROR if the method succeeded, including the case that no application was defined at the specified path. If the method fails, other error codes converted to HRESULT will be returned.