If your printer worked normally until you installed a Telstra Smart Modem 4, the printer may not be broken and the Wi-Fi password may not be wrong. The modem introduces Wi-Fi 7, WPA3 security, band steering and a combined wireless network that some older printers cannot handle reliably.
This is a specific compatibility problem that can appear immediately after a Telstra modem replacement. The internet works, phones and newer computers connect, but the printer refuses to join the network or disappears from every computer in the house.
If the problem began with a modem change, the correct starting point is usually printer help after a modem replacement, not repeatedly reinstalling the printer software.
Why the Telstra Smart Modem 4 can cause printer problems
The Telstra Smart Modem 4 is a dual-band Wi-Fi 7 modem. Its newer wireless features are useful for compatible phones, laptops and other modern devices, but printers often use much older and more limited Wi-Fi hardware.
A printer may support ordinary 2.4GHz Wi-Fi while struggling with the way the new modem presents or secures that network.
- πΆ Wi-Fi 7 mode: An older printer may not negotiate correctly with the modem while its wireless radios are operating in Wi-Fi 7 mode.
- π WPA3 security: The printer may recognise the network but fail during authentication, even when the password is correct.
- βοΈ Band steering: The modem combines its 2.4GHz and 5GHz networks and attempts to direct each device to the most suitable band.
- π¨οΈ Older printer limitations: Many printers only support 2.4GHz, older security modes and basic wireless discovery.
- π» Stale computer connections: Even after the printer reconnects, Windows, macOS or scanner software may continue looking for its old network address.
The result can look like a printer fault, a password problem or a failed driver installation when the real issue is the modem’s wireless configuration.
First confirm that you are using the correct network
Before changing advanced settings, confirm exactly which Wi-Fi network the printer is trying to join. A new modem normally has a new network name and password unless the original details have been copied across. If those details changed, start with the steps for updating a printer after changing the Wi-Fi name or password.
- β Check the Wi-Fi name and password printed on the Telstra Smart Modem 4.
- β Make sure the printer is not still trying to connect to the previous modem’s saved network.
- β Confirm that the phone or computer used for printer setup is connected to the same main network.
- β Avoid connecting the printer to a guest network, as guest devices may be prevented from communicating with computers on the main network.
- β Remove or forget failed Wi-Fi details from the printer before starting another connection attempt.
If the printer sees the correct network but repeatedly rejects the password, drops out during setup or never completes the connection, wireless compatibility becomes the more likely cause.
Test Wi-Fi 6 when Wi-Fi 7 causes compatibility trouble
Wi-Fi standards are designed to be backwards compatible, but that does not guarantee that every older printer will work properly with every new modem configuration.
A useful first compatibility test is to change the Smart Modem 4 wireless mode from Wi-Fi 7 to Wi-Fi 6. This preserves a modern wireless network while removing one layer of complexity that older printer hardware may not handle correctly.
Do not change every modem setting at once. Apply the Wi-Fi 6 change, allow the modem a few minutes to settle, and then try connecting the printer again.
If the printer connects at this stage, the fault was not the password or printer driver. It was the interaction between the printer’s wireless hardware and the modem’s Wi-Fi 7 configuration.
WPA3 may reject an older printer even with the right password
The Smart Modem 4 uses WPA3, the newer Wi-Fi security standard. Some printers support WPA2 but cannot connect reliably to WPA3 or a newer mixed-security environment.
This can produce a particularly confusing symptom: the printer detects the network, accepts the password entry and then reports that it cannot connect. Entering the same password again does not solve the underlying security mismatch.
If changing to Wi-Fi 6 does not restore the connection, the next staged test may be WPA2 PSK. On the Smart Modem 4, the wireless mode may need to be changed to Wi-Fi 6 before the WPA2 option becomes available.
Reducing wireless security should not be treated as a casual permanent fix. The purpose of the test is to identify whether WPA3 compatibility is the reason the printer cannot connect, then decide on the safest practical configuration for the household.
Band steering can hide the 2.4GHz network the printer needs
Most wireless printers use 2.4GHz Wi-Fi. The Telstra Smart Modem 4 also provides 2.4GHz, but band steering normally combines the 2.4GHz and 5GHz bands under one network name.
Modern devices can usually negotiate this automatically. Older printers and printer setup apps may not. They can fail to detect the correct band, refuse to complete setup or become stuck while the phone is using 5GHz and the printer is trying to use 2.4GHz.
On the Smart Modem 4, band steering cannot be disabled while Wi-Fi 7 remains enabled. The practical order is therefore important:
- 1οΈβ£ Change the modem wireless mode from Wi-Fi 7 to Wi-Fi 6.
- 2οΈβ£ Apply the change and allow the modem to finish updating.
- 3οΈβ£ Test the printer before changing anything else.
- 4οΈβ£ If necessary, disable band steering so the 2.4GHz and 5GHz networks can be managed separately.
- 5οΈβ£ Connect the printer specifically to the 2.4GHz network.
- 6οΈβ£ Keep the setup phone or computer on the main network while completing printer installation.
Separating the bands is not always required. It is a diagnostic step for printers that cannot cope with the modem’s combined network or automatic band selection.
Use a staged troubleshooting order
The most reliable approach is to change one variable at a time. This shows which setting caused the failure and avoids leaving the entire household network unnecessarily altered.
- π Confirm the network: Check the new Wi-Fi name, password and whether the printer still remembers the previous modem.
- π Restart properly: Restart the modem and printer before changing advanced settings.
- π‘ Test Wi-Fi 6: Downgrade the wireless mode, apply the change and test the printer again.
- π Check WPA compatibility: Test WPA2 only if the printer still cannot authenticate.
- βοΈ Review band steering: Disable it only when the printer needs a separately identifiable 2.4GHz network.
- π¨οΈ Reconnect the printer: Remove the failed network details and join the corrected network from the beginning.
- π» Repair each device: Update printer, scanner and computer connections after the printer is back online.
This staged method is more useful than repeatedly pressing WPS, reinstalling applications or factory-resetting the printer without first confirming that the modem configuration is compatible.
The printer can reconnect but still show as offline
Restoring the printer’s Wi-Fi connection is only the first half of some jobs. The new modem may assign the printer a different local network address, while computers continue sending print and scan requests to the old one.
- π₯οΈ Windows printer queues: The existing printer entry may still use an old TCP/IP address or failed discovery port.
- π Mac and AirPrint discovery: The Mac may retain an unavailable printer entry even though the printer has rejoined Wi-Fi.
- π Scanner software: Printing may return while scanning still searches for the printer at its previous address.
- π± Phone applications: The manufacturer’s app may need the old printer removed and rediscovered.
- π’ Multiple computers: Each computer may have its own stale printer connection and require separate repair.
A printer that is connected to the modem but still appears offline is no longer primarily a Wi-Fi password problem. The computer may still be using the printer’s old network address, so its saved connections, ports and discovery records need to be checked across the devices that use it.
Avoid changing everything at once
It is tempting to factory-reset the printer, modem and every computer when nothing appears to work. That can remove useful information and create several new problems without identifying the original one.
- β οΈ Do not assume repeated password failures always mean the password was entered incorrectly.
- β οΈ Do not reinstall printer software before confirming that the printer itself has joined the modem.
- β οΈ Do not place the printer on guest Wi-Fi if computers on the main network need to use it.
- β οΈ Do not disable several security and wireless features simultaneously unless you have recorded the original settings.
- β οΈ Do not factory-reset the Smart Modem 4 as the first troubleshooting step.
The aim is not simply to make the printer connect once. It is to establish a stable configuration that allows the printer, scanner, computers and mobile devices to keep finding one another.
When it needs proper printer and Wi-Fi troubleshooting
If your printer stopped working after a Telstra or other modem replacement, PcRiot can check both the modem configuration and the printer connections across your devices.
This can include identifying the printer’s wireless limitations, testing Wi-Fi 6 and WPA compatibility, reviewing band steering and 2.4GHz settings, reconnecting the printer, repairing stale Windows or Mac printer entries, and restoring scanner access.
PcRiot provides onsite Perth printer and Wi-Fi help for home users and small businesses when a previously working printer stops after a modem change.