Replaced Dsl With A Cellular Hotspot... Causing Issues.

Hello to all,
It always feels good NOT to be on here (ie no problems!!), and yet, really great to know where I can find friendly, helpful support.. or at the least, hear the laughter. Recent events make this a more somber meet-up. Condolences to all.

Hopefully, I can find some help for a computer problem. Dell Optiplex 7010, running Win 7 Pro, MS updates are turned off, (because I have several programs that apparently don't run on Win 10). MalwareBytes Prem. Previously on DSL, that service was terminated.. so I opted to add a cellular hotspot, wired to my desktop, and wi-fi to my phone. Both work, sometimes. Purchased a NetGear Nighthawk MR1100-1A1NAS. Not 5G, but I don't need speed. AT&T provider with 50G of data/mo (no problem).. but impossible to get English speaking support (or any for that matter).

The obvious. I'm over the hill. Both literally and figuratively! I bought a external antenna, with decent gain, but it is omni-directional. Signal strength goes between none, to RSRP of -114 dBm. It will continue to work, down at -120 to -122! I may purchase a yagi, if that proves to be the problem. Speedtest has done 20mbps (tops) download, but typical it's more like 1-2mbps average. Upload.. yes, sometimes! I'm not a gamer or streamer, 1-2 could be just fine, except the problems may be preventing truly proper/faster data. I used to have a up down speed indicator, but that apparently doesn't work with this hotspot. So I'm never sure of the data speed, but very slow, or never, to load, is the big indicator. No idea if this thing is truly secure.. any suggestions to do a malware check? I don't suspect that is the prob.

Windows shows a center page error block, that says two devices have the same IP. My extensive install included inserting the sim, then attaching antenna, power, Ethernet cord, and pushing the on button. I've looked all over the possible (basic) diagnostics, which don't lend any answers, or pointers. I have Tweaking.com, but don't know if running it will activate MS updates. The occasional warning on a recent upload test said socket error. Several web sites don't work, and report, "Your internet connection is slower than we expected". Duh!! In looking at some of the error logs, Boot issues look troubling.. but likely a completely different issue to address asap. maybe? I may be in the wrong forum. Any assistance, as always, is greatly appreciated. I sent coffee.

 

Any suggestions here at all? Did I post this in the right forum? Does anyone know what tests I'd need to run to determine what Win 7 has located, which says that I have two devices with the same IP? Is there a better approach to solving these problems? I'm paying AT&T for their cellular data.. it's just that their tech support has been impossible to reach, to speak with anyone, or knowledgeable. I don't have the benefit of my own personal IT department to keep things running properly. And my experience with AT&T, AND with cellular hotspots, has a very limited knowledge base.
Thanks for any good ideas. Jerry

 

In Windows open CMD - Hit Win + R, in open type CMD. When that opens type ipconfig...that will tell you the IP of the computer, then open your phone and look around settings and see if you can find the IP there.
You can scan the network with something like https://borntoberoot.net/NETworkManager/Download.

A cell modem will never give you anymore than 1-2Mbps up. They expect the majority of the traffic to be down stream, Netfilx, Hulu... not you hosting an FTP.. Tmobile gave us a new 5G modem and one, it would not work at my home and two, the slow upload was a reason to return it. That and it was supposed to be geo located at my residence, so I couldn't take it with me and use it at other places.

Looked for cell boosters? IDK if they work the same for 5G.