What do I do to connect my computers to new modem?

Got a bad modem. Bought a new modem. Same router. Now my laptops nor iPhones will connect to the internet without a password. I live in the middle of nowhere so I didn't password protect the router or the modem. What do I do now? How do I fix this?

You may need to properly configure your new modem. Please contact your Internet service provider if you're not familiar on how to do that. If that's done, and you're still prompted to enter a password when getting online with your wireless devices, then it's possible that your router's reconfigured. There are wireless routers with a button on which the wireless security settings are changed when that button is pushed.

Did you buy just a modem (only one Ethernet jack) or did you buy gateway (multiple Ethernet jacks).

Many devices sold today are combination modem and router units commonly called gateways.

If this is the case they have their own Wi-Fi SSID. Sometimes they are password protected by default. If this is the case there's usually a sticker on the router with the default SSID and password.

If you did buy a standalone modem and connected it to your existing router then nothing should have changed. If the Wi-Fi was unsecured (open) it should have stayed that way, adding a new modem has no effect on the Wi-Fi security settings of the router.

That being said,

In either case, you can log into the router and view or change the Wi-Fi security settings.

Download the router manual if you don't have one. You'll have to do a Internet search for your specific model and include the terms "manual" or "setup" in your search.

Connect a PC or laptop via Ethernet to one of the router's LAN ports and follow the instructions in the manual to set it up.

If you don't know the administrative login password, you'll have to reset the router to factory default state. The reset button is usually behind a small hole on the back of the router. To reset the router, use a toothpick or similar object to depress the button for several seconds while the router is powered up. If the router is reset to factory default, thus erasing all user modified settings then it will revert to the default passwords and settings.

After resetting the router you'll want to change the default administrative password and reconfigure the wireless security settings.