The printer is always offline when connected to WiFi, and loses connection after changing the router. Ninety percent of the cases are due to these three reasons.

At around nine o'clock in the evening, my wife handed over a review material and asked me to type it out for my child to use tomorrow. I clicked on Print, but the progress bar didn't move at all, the printer icon was gray, and there were two words in the status bar.: Offline. I bought the Epson L3158 at home three years ago. I don’t use it more than ten times a year. Every time I use it, it breaks down. This time I kept an eye out and wrote down the entire troubleshooting process. I found that there were three reasons for the printer being offline, each one less mysterious than the last.

Take five minutes to figure it out first: Is it disconnected or disconnected?

This step is the easiest and easiest to skip. There are two completely different ways to take your printer offline: One is that it is not connected to the Internet, and the other is that it is well connected to the Internet and cannot be found on your computer. The direction of cultivation is thousands of miles away.

First look at the light on the printer. A machine like the L3158 without a screen relies entirely on the WiFi light to speak: The WiFi light is always on, indicating that it thinks it is on the network ； The WiFi light flashes slowly, indicating that it is looking for a network ； The light is off, it means it's not connected. Then turn on your mobile phone and enter the router's backend, look through the list of connected devices, and find a device whose name starts with EPSON - I do this step first every time I check. It is much faster than messing around with the driver. I have written an article before about how to read the router status page. Interpretation of running status page , the device list is in the same backend.

My family was stuck on the first line that night. EPSON is clearly online in the device list, and the IP is 192.168.31.66 . My heart skipped a beat: It's broken, and the port on my computer still points to the old address.

The real murderer: The IP has moved, but the computer is still pointing to the old house number.

This is the largest proportion of offline faults, especially after changing the router. The principle is explained in one sentence: When installing the printer driver, Windows nailed it to an IP, and this IP was written into the printer's TCP/IP port. ； Later, the router was changed, or the DHCP lease expired and was reassigned, and the IP assigned to the printer changed, but the port on the computer was still pointing to the old house number. No one answered the door, so it reported offline.

This is the one I have at home. It turns out that it has always been there 192.168.31.108 , the router had a power outage last month, and after restarting, DHCP redistributed the address pool, and the printer was squeezed to 31.66. The computer doesn’t know, but it’s still knocking on the 108 door over and over again.

The repair is very simple. First ping it to make sure it is alive.: Press Win+R on the computer, enter cmd and press Enter, then type ping 192.168.31.66 , if it can be connected, it means the machine is online. Then open the Control Panel, Devices and Printers, right-click the printer and select Printer Properties, switch to the "Port" tab, select the original Standard TCP/IP Port and click "Configure Port", change the IP address from 31.108 to 31.66, confirm, and print another test page. It didn't take more than three minutes here.

Simply repairing the port is a temporary solution, and it may be moved next time there is a power outage. Just one cure: Go to the backend of the router and pin the printer to an IP, bind it statically through DHCP, fill in the MAC address, and choose a position on the edge of the address pool for it. I have made a list of which network equipment in my home must be statically bound, and the printer is ranked first. Just follow it. See for details. Static IP binding article . After binding this printer, it has not been offline again for three years - until this time, because it was connected to an old router, the binding rules were not transferred after the switch.

By the way, I have written about the process of replacing a new router before. The core one is to copy the WiFi name and password from the old one, so that the whole family of devices can switch without any problem. That article is in here . But the printer is the exception to that article: Even if it connects to the new router by itself, the computer port still needs to be cleared manually. This is where it is more difficult to handle than the sweeper camera.

The real murderer two: The printer's network card only recognizes 2.4G, and the dual-band combination is confusing.

My colleague Lao Zhang bought a new HP DeskJet 2729 last month to mark papers for his children. After a whole night of configuring the network and failing, he asked me on WeChat. His symptoms are typical: HP Smart is installed on the phone, and the App can search for the printer, but when it comes to selecting WiFi, it fails. Either the WiFi name cannot be found, or the connection is disconnected after a second.

I asked him if your router is dual-band. He said yes, the same name works fine on both phones. Herein lies the problem. Home printers on the market, whether Epson, HP or Brother, have network cards of the same generation as sweepers and cameras, and only recognize 2.4G. A dual-band-in-one router will broadcast 2.4G and 5G under the same name. Smart devices like mobile phones will choose the frequency band on their own, but printers will not be able to connect. Either they will not be able to connect, or the signal will be weak. I have written about the troubleshooting of the distribution network of the sweeper. The logic is exactly the same. That article is in here .

There are two ways to solve this problem. the easy way: When configuring the network, temporarily separate the dual-band into one, give 2.4G a separate name, connect the mobile phone to 2.4G and then configure the printer. After the configuration is completed, put the dual-band back together. Each router has different names for how to separate the frequency bands. I have compiled an article Dual-band separate settings You can copy it. thorough road: Just leave an unmerged 2.4G name for the printer. It doesn’t need the speed of 5G anyway. The first route Lao Zhang took was to complete the allocation in ten minutes after unpacking the frequency bands. He was so angry that he said that he had spent the whole night in vain.

The third murderer: If you change the WiFi name or password, you need to manually reconfigure the network.

My sister's house got a brand new router when she got a broadband replacement, and the installer came up with a new WiFi name to save trouble. On that day, all the family's mobile phones and computers were connected, and everyone was happy. On the third day, when they were trying to type something, they discovered that the printer was disconnected. This is the most straightforward one: The network name or password has changed, the printer doesn't recognize the new network, and no one has entered the new password for it, so it can't get in.

There are only three methods for reconfiguring the network for a printer without a screen. I have tried them all for my family members.:

The first one is WPS one-click provisioning. Press and hold the WPS button on the router for about two seconds, and then press the network button on the printer. The printer WiFi light will change from flashing to solid light. The fastest, but the premise is that your router’s WPS is turned off, and many people turn this function off for security reasons. I have done some math on whether to turn it on or not. WPS principle , decide for yourself after reading it. My approach is to temporarily turn on the configuration and then turn it off.

The second one is direct connection with the mobile app. Install Epson Printer Finder, follow the prompts to enter the wireless direct connection of the printer, connect the mobile phone to the temporary network starting with Direct sent by it, select your home WiFi in the App, enter the password, and you are done. HP's counterpart is HP Smart, for the same reason. This route does not require touching the router, which is suitable for routers like my sister's which are out of reach in weak current boxes.

Article 3: Computer USB cable configuration. Download the installation program from the random CD or the official website. Connect the printer to the computer with a USB cable. Select wireless connection during the driver installation process, and it will write the WiFi currently connected to your computer into the printer. The dumbest but most stable, use it to end when the first two fail.

Another reminder, the chain reaction of changing the WiFi name is greater than imagined. I once made an account of reconfiguring smart devices one by one. Rules for changing your name , take a look before doing anything, which can save a lot of trouble. The same goes for passwords. I have also tried three ways to change passwords. This article inside.

Three trivia facts, picked up on the way to repair the printer

first one: The printer has its own web backend. Enter its IP directly in the browser address bar, for example http://192.168.31.66 , you can enter a simple but sufficient management page, in which the ink level, signal strength, and firmware version are all listed. When troubleshooting signal problems, taking a look at the signal strength reported by it is much more accurate than guessing. After configuring the network, add it to your browser bookmarks and check if it is still there next time you are offline.

second: Queue stuck is not a network problem. One time, the printer ran out of paper and jammed. After adding paper, it stopped printing, and the task still couldn't be deleted. It was stuck in "Deleting". This is a problem with the Windows print background service and has nothing to do with WiFi. Win+R, enter services.msc and press Enter, find Print Spooler, right-click to stop it, then go to the C:\Windows\System32\spool\PRINTERS directory to clear the remaining task files, then go back and start the service, and the queue is instantly clean. I use this trick two or three times a year, and it works every time.

third: The less you use it, the more likely it is that something will happen. If the printer is not powered on for a long time, the network status in the cache will be dead, and the router will not know what has changed. My current habit is to plug it into the same socket as the router. When the router is powered on, it will be powered on. Don't let it be deeply powered off for more than a week. In addition, the method of connecting the USB port of the router to the printer is another matter. It does not conflict with the built-in WiFi of this printer. If you want to know more, read what I wrote before. Printer connected to router .

Take your seats according to the number, and give an order at the end.

Just five steps in sequence: Look at the lights, check the router device list, ping its IP, change the port or reconfigure the network, bind a static IP and call it a day. That night, it took me less than half an hour from the time I found out I was offline to typing out the review materials, of which 20 minutes were spent finding the new address 31.66. There is no need to be afraid of printers. The problems they cause are much more stupid than routers. If the three real culprits are to deal with each other one by one, one of them will always be able to deal with them.