The short answer
Nearly every printer is 2.4 GHz only. If your router broadcasts both bands under one name, the printer often cannot complete setup. Split the bands into separate names, connect the printer to the 2.4 GHz one, then give it a reserved IP address so it never disappears again.
Wireless printers have a reputation for being temperamental, and it is deserved, but the causes are consistent enough that you can work through them methodically. Almost all of them come down to the network rather than the printer.
The five reasons, in order
1. The printer cannot see a 2.4 GHz network
Printers use 2.4 GHz almost universally. When a router presents both bands under a single name, the phone running the setup app may be on 5 GHz, and the printer simply never finds the network it is being told to join. This is the single most common cause of a setup that fails at the last step.
Fix it by giving the 2.4 GHz band its own network name in the router settings, then joining the printer to that explicitly. If you would rather not split them permanently, switch the 5 GHz band off for ten minutes while you complete setup.
2. The IP address keeps changing
A printer that worked yesterday and is “offline” today has usually been given a different IP address by the router, while your computer still has the old one saved in its printer port. This is why the classic fix of deleting and re-adding the printer works — and why it stops working again a few weeks later.
The permanent fix is a DHCP reservation: in the router’s LAN settings, find the printer and assign it a fixed address. Do this once and a whole category of printer problems disappears.
3. The password was typed on a printer keypad
Entering a long password with arrow keys on a small screen produces errors constantly, especially with case-sensitive characters and symbols. If setup reports a wrong password and you are sure it is right, this is a likely explanation. Use WPS if both devices support it, or use the manufacturer’s phone app, which passes the credentials across directly.
4. Router features that block it
Several common router settings stop printers working even when the printer is connected:
- AP isolation or client isolation prevents devices on the network from talking to each other. Your printer joins the Wi-Fi happily and remains invisible to every computer. It is often on by default on guest networks — so never put a printer on a guest network.
- MAC filtering blocks the printer if its address is not on the list.
- WPA3-only security locks out older printers that only speak WPA2. Setting the router to WPA2/WPA3 mixed mode resolves it.
5. It is genuinely out of range
Printers usually live in the least convenient corner of a house, often on the floor, often behind furniture. Their antennas are small and their transmit power is low. Check signal strength from the printer’s own network menu rather than assuming.
Getting it back online
Power cycle the printer and the router
Switch the printer off at the mains, not just the front button, and unplug the router for 30 seconds. Bring the router up first and let it settle for two minutes, then the printer. Ordering matters because the printer requests its address at startup.
Print the network configuration page
Nearly every printer can print a network status or configuration page from its menu, and it is the most useful diagnostic available. It shows whether the printer has an IP address, which network it has joined and its signal strength. An address starting 169.254 means it failed to get one from the router.
Make sure it is joining the 2.4 GHz network
Split the bands in your router settings if they share a name. On the printer, run wireless setup again and pick the 2.4 GHz network specifically.
Reserve its IP address
In the router, find the printer in the connected devices list and assign a DHCP reservation. Then, on your computer, remove the printer and add it again so it picks up the fixed address.
Turn off AP isolation and check the security mode
In the wireless settings, make sure AP or client isolation is off for the main network, and set security to WPA2/WPA3 mixed rather than WPA3 only.
Reinstall the printer on the computer
On Windows, Settings, Bluetooth and devices, Printers and scanners, remove the printer, then Add device. On a Mac, System Settings, Printers and Scanners, remove with the minus button and add again. Choose the driver-based entry rather than a generic one where offered.
If the printer sits near the router, use an Ethernet cable. Wired printers essentially never develop connection problems, and every computer on the network can still print to it wirelessly. It is an unglamorous answer that solves the problem permanently.
Frequently asked questions
Why does my printer keep going offline?
Usually the IP address changed, so the computer is still looking for it at the old one. A DHCP reservation in the router fixes it permanently, unlike deleting and re-adding the printer which only fixes it until the next lease renewal.
Can a printer connect to 5 GHz Wi-Fi?
A small number of recent models support both bands, but the vast majority are 2.4 GHz only. If your network hides 2.4 GHz behind a combined name, the printer will struggle regardless of how close it is.
What does an IP address starting with 169.254 mean?
The printer asked the router for an address and got no reply, so it assigned itself a fallback. It means the join failed — check the password, the band and whether the router’s address pool is full.
Should I put my printer on the guest network?
No. Guest networks normally enable client isolation, which stops your computers reaching the printer at all. Keep the printer on the main network.
Split the bands, reserve the address, and check AP isolation. Those three cover the large majority of wireless printer problems.
