The short answer
The usual cause is that the printer’s IP address changed and the computer is still looking for it at the old one. Give the printer a fixed address in the router, then re-add it on the computer. That one change stops the problem recurring, which restarting everything does not.
A printer that says offline while its own screen shows a healthy Wi-Fi connection is one of the most common and most irritating home tech problems. The reason it keeps coming back after a restart is that restarting fixes the symptom by accident and leaves the cause in place.
Why it happens
When the printer joins your network, the router hands it an address from a pool, valid for a set period known as a lease. Your computer then stores that address in the printer’s configuration. If the printer is off when its lease expires, or the router restarts, the address can be reassigned, and the printer comes back on a different one. Your computer is still sending jobs to the old address, receives nothing back, and marks the printer offline.
Everything else in the list below is a secondary cause. Fix the address and most people never see the problem again.
The permanent fix
Find the printer's current IP address
Print a network configuration page from the printer’s own menu, usually under Settings, Network, or Reports. It will list an address such as 192.168.1.47 and the MAC address.
Log in to the router
Type the router’s address into a browser, commonly 192.168.0.1 or 192.168.1.1. The admin password is usually on a sticker on the router and is not the Wi-Fi password.
Find DHCP reservation
It may be called Address Reservation, Static Lease, DHCP Reservation or Fixed IP, and it lives under LAN, DHCP or Advanced settings.
Reserve the printer's current address to its MAC address
This tells the router to always give that printer the same address. It is more reliable than setting a static address on the printer itself, because the router then knows the address is taken.
Restart the printer
It will request an address and receive the reserved one.
Remove and re-add the printer on each computer
Delete the existing printer entry, then add it again so the computer stores the correct, now permanent, address.
If your router has no reservation feature, set a static address on the printer instead, choosing one outside the router’s DHCP pool. If the pool is 192.168.1.100 to 192.168.1.200, pick something like 192.168.1.50. Choosing an address inside the pool causes conflicts later.
Other causes worth checking
Use Offline mode is ticked
On Windows, open the printer queue, click the Printer menu, and make sure Use Printer Offline is unticked. Windows sets this automatically when it cannot reach the printer, and it sometimes fails to clear it afterwards. Clear the queue of stuck jobs while you are there, because a failed job at the front blocks everything behind it.
The print spooler is stuck
Open Services, find Print Spooler, and restart it. For a thorough reset, stop the spooler, delete everything inside the printers folder in the Windows spool directory, then start it again. This clears corrupted jobs that survive a normal restart.
The printer is on a different network
Check that the printer and computer are on the same network, not one on the main network and one on a guest network. Guest networks isolate clients from each other by design, which makes the printer invisible even though both have working internet. This happens most often after someone reconnects the printer using a phone that was on the guest network.
Wi-Fi Direct is interfering
Many printers broadcast their own network for direct printing. If a computer has ever connected to that, it may have the printer configured through it rather than through your router, and that connection disappears when the computer joins your normal Wi-Fi. Remove the printer and add it again over the network, not over Wi-Fi Direct.
Power saving on the printer
Deep sleep modes on some printers drop the network connection entirely rather than maintaining it. The printer wakes when you press a button but not when a print job arrives. Look for a sleep timer or eco setting and extend it, or disable the deepest sleep level.
Firewall or antivirus
Security software updates occasionally reclassify the local network as public and block printer discovery. Check that your network is set to Private in Windows network settings, and that the firewall allows File and Printer Sharing on private networks.
Avoid the temptation to reinstall the manufacturer’s full software suite as a first step. It rarely fixes an address problem, it installs a great deal of background software, and on Windows the built-in driver is usually sufficient and more stable. Reinstall only if the driver itself is genuinely broken.
Making printing more reliable in general
- Wire it if you can. Most home printers have an Ethernet port, and a printer that lives near the router should use it. Wired printers stop being a problem entirely.
- Check the Wi-Fi signal where the printer sits. Printers are often in corners, cupboards or spare rooms with weak coverage, and their antennas are poor. A marginal signal produces intermittent offline status that looks random.
- Use 2.4GHz. Most printers only support it, and the ones that support 5GHz rarely benefit, since printing needs almost no bandwidth.
- Keep the firmware updated, but be aware that some manufacturers use firmware updates to enforce cartridge restrictions. Read the release notes if you use third-party ink.
Why does my printer go offline every few weeks?
Almost always because its IP address changed when the lease expired or the router restarted. A DHCP reservation in the router fixes it permanently.
Why can my phone print but not my laptop?
Phones usually print through a discovery protocol that finds the printer by name each time, while computers store a fixed address. That is why the phone adapts to an address change and the laptop does not.
Should I set a static IP on the printer or reserve one in the router?
Reserve it in the router. That way the router knows the address is in use and will not hand it to another device, which is the failure mode of manually set static addresses.
Does restarting the printer and router actually help?
It restores service temporarily by forcing a fresh address assignment that happens to match. It does nothing to prevent it recurring, which is why the problem comes back.
My printer works for one computer but not another. Why?
Each computer stores its own configuration. The one that works has the current address; the other still has the old one. Remove and re-add the printer on the affected computer.
The short version
Print a configuration page to get the address, reserve that address in the router against the printer’s MAC address, then remove and re-add the printer on your computers. Untick Use Printer Offline, clear the queue, and confirm both devices are on the same network rather than one being on the guest network. If the printer sits near the router, plug in Ethernet and the whole category of problem disappears.
