iMac switching networks
I Googled how to delete networks from my iMac but it's not working.
When I go to the network icon top right on the menu bar it shows all the networks in my area, including mine which is at the top of the list. All of the networks listed seem to be password protected (including mine) but there is one called Netgear and it's not password protected. My computer switches to this network a few times a day. I don't know who's it is and I'm afraid someone is going to use it to see my password for my 1Password account and then have access to all my financial stuff. Scary.
I went to Network Preferences, then advanced, highlighted that Netgear network, and I deleted it. But when I go to the dropdown box top right on the menu there are 11 networks listed there. And the Netgear one I deleted is still there and my computer still switches to it. However in that Preferred Networks window it only shows my network, my iPhone, and my next door neighbors network now.
I want to know why all of the networks listed in the top right network dropdown are (11) not listed on my Network preferences box in System preferences (that lists only 3)? And why when I delete the Netgear network it keeps coming back and still changes over to it? Should I be concerned, can someone steal my passwords this way?
I'm running High Sierra 10.13.6
Any help would be greatly appreciated. Oh and as a final note I don't think my modem is turning off (it's comcast combo modem and wifi) the reason I am pretty sure it's not turning off is I only have steaming TV (hulu, netflix and DirectTVNow) and I have MSNBC on most of the day and if the network stopped working my TV stream would hiccup, right?
Susan
iMac, macOS High Sierra (10.13.6), iphone 8, ipad, Apple TV, Macbook