MR1100 install issue, Win 7 Pro reports Network Error, 2 devices with same IP

[nongeek12]

Limited knowledge here on Hotspots, and Networks.

Purchased MR100 1N1NAS, signed up for hotspot data, added SIM card, and eventually connected Ethernet cable to desktop computer running Win 7 Pro.  Data speeds have been as high as 20Mbps, but typical speedtest shows average download of 1-2 Mbps.  RSRP shows from -113dBm to -122 before it stops receiving.  I have a "high gain" remote antenna, but it's omni directional, not a yagi.  And I don't know if ATT simply slows the data.  I'm well below the 50G premium plan usage.  Most web sites will load, most are slow, and some become useless, being way too slow.

Can anyone help me with the proper setup, as that appears to be a primary point of contention.  Help is greatly appreciated!

[nongeek12]

Additional info:  Dell Optiplex computer.  Ethernet cable connection between router and computer,  Aux power for battery charging.  My cell phone will connect to the WiFi of the router, but data rates are slow.

[nongeek12]

Sorry, typo in first post... this is a MR1100 Nighthawk mobile router

[nongeek12]

Uh...

The recommendations posted below my previous questions were all for different devices.  This is a NetGear MR1100 hotspot in a Win 7 Pro system, plugged into lan ethernet direct to computer, with Wi/Fi connecting to my iPhone.

The computer (and Lan) are having terrible problems, very slow, very unreliable.

Speedtest "typically shows" 0.18 MBPS!  On occasion I'll see 2 MBPS.. but I have seen as high as 20 MBPS.  No idea if ATT is just being a jerk, and has my data speed turned down.  The signal in dBm looks strong enough.  Win 7 shows a window, mid-screen that says Warning 2 devices have the same address.

So.. this could be a bad MR1100.  Could be a bad install. Could be a Windows conflict.  Could be 1 bar signal.  Could be ATT dragging it's feet.  How do I go about sorting the problems, or finding a community volunteer who can direct me with A, B, Cs.. of changing stuff to make it work??  All of the stuff posted in other recommendations, is just confusing.  Thanks!