The light flash Installation on a so-called WPS button on the router does not work before because it does not exist on such a (new!) T-Online routers. So then just the online installation on the TP-LINK network. Very easy, I thought. Far from it, because even after downloading the manual from the TP-LINK service and installation tests with three restarts the repeater there was no connection to the Speedport. Pity! Obviously you have to Fritz & Co. have in-house so this is profitable acquisition. Have it returned. The two points are just because the device itself works well determined. Just not with my Speedport.