Can anybody direct me to a program that I can install on Windows 8.1 to detect intruders. Or give me any advice on how to look for intruders within Windows. My Wifi used to be no problem and was quite fast. Now I constantly have to reset it. Speed has gone right down. I searched on the net and I found this program. Who's on my Wifi. But haven't installed it yet. Thanks in advance and Kind Regards.