I upgraded my SP3 to Windows 10 and shortly thereafter automatic updates installed the January update. While the WiFi works, it only works if the SP3 is sitting in the same room as the router. It used to be fine sitting in the lounge some 10 + metres away and now it won't connect or is extremely slow. An iPad in the same location is fine as are my windows phones!! A "sfc /scannow" run claims there were corrupt file errors that it could not fix. The errors relate to a file "opencl.dll" and the rest reference files that are "not owned" or have duplicate ownership. But basically everything works fine apart from that. I have tried re-installing the WiFi drivers to no avail. There is also one other interesting issue, the surface can ping all the computers in the home network, but no one can "ping" the surface it returns a timeout error. Even when I initiate the ping from the router it still times out, yet internet access is fine as long as you sit next to the router! Any suggestions would be welcome and while a "clean install" is not ruled out it's not that simple because my original UK purchased Surface had a screen fault and was replaced by Microsoft; but because I was living in Spain I had to take one with Spanish language and all the hassle of installing all the language and voice packs to make it "English" is something I would like to avoid!!