Though the air card is set to DHCP, the computer, print server, and the like may be DHCP or Static.
Now sometimes, when you first connect if the router portion of the MiFy card is not all that great it may well try to assign two devices the same IP, this can cause issues, but hopefully it should auto-adjust.
If you know how (NOTE: I DO NOT HAVE A MI-Fy card) you can access the router portion of the card from your browser.. I can give you hints but this is kind of going high level. the easy way is to RTFM.
You should be able to get a DHCP client list.
And from this my may find the path to knowledge.
My set up here I've een it one time.
I then made an administrative change to my router. and .. It went away.
One suggestion. Verizon Mi-Fy cards ship on channel six, Change the channel to something else, say 10, or 2, also change the SSID, Do not use your name but use something else. Mine is descriptive, but unless you know the joke, you won't get it.
Nothin adds excitment like something that is none of your business
Kenwood TS-2000 housed in a 2005 Damon Intruder 377
Seems we have made assumptions, at I have. I did not see this as a MiFi issue, as I thought you would have mentioned that. What Verizon Air Card do you have? Have you run a "ipconfig/all" in a command prompt on yours and your fiance's computer? Any duplicate IPs listed.
If it is a MiFi, wa8yxm has a good course of action. Log into your MiFi admin page and look at all of the wireless connections and DHCP issued. Any dupes?
May God bless your travels
Me, The Wonderful Wife
and two Spastic Border Collies U.S. Army Retired 2013 Tiffin Allegro 36LA 2007 Saturn Outlook, FROG