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Common problems for Connectivity Issues
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‎02-03-2026 04:15 PM

HP Recommended

6400 will not connect to the wifi anymore I have reset everything and delete and tried to reinstall the printer but now it can’t find it. What else is there to do. It was just working yesterday with no problem. Please advise it’s not that old

1 person had the same question
1 ACCEPTED SOLUTION

Accepted Solutions

‎02-05-2026 08:58 AM

HP Recommended

Hi @Jedi3,

 

Welcome to the HP Support Community.

 

Thank you for posting your query.

 

I am sorry that hear that your HP printer is unable to connect to Wi-Fi and was working previously, I would request you to please follow the steps:

 

Power Reset

  • With the printer ON, unplug the power cord.
  • Wait 60 seconds.
  • Plug directly into a wall outlet (avoid surge protectors).
  • Restart your router as well.

Restore Network Defaults

  • On the printer control panel:
  • Press and hold Wireless + Cancel for 5 seconds.
  • This clears old Wi‑Fi settings.
  • The wireless light should start blinking

Enable Wi‑Fi Setup Mode

  • If the printer has a touchscreen:
  • Go to Setup → Network → Restore Network Settings.
  • If button‑based:
  • Hold the Wireless button until the light blinks.
  • The printer is now discoverable for ~2 hours.

Reconnect via HP Smart App

  • Install HP Smart on your phone or PC.
  • Tap Add Printer → select your HP 6400.
  • Enter your Wi‑Fi SSID and password.
  • Wait until the wireless light turns solid

Update Firmware

  • Connect the printer via USB to your PC.
  • Download the latest firmware from HP’s support site for the 6400 series.
  • Run the update utility — this often fixes sudden Wi‑Fi dropouts.

Re-add the Printer:

  • On your computer, go to "Devices and Printers" (or similar menu) and remove the printer. 
  • Then try re-adding the printer using the "Add a printer" option, ensuring your computer is on the same network.

Change Network Settings:

  • Check if your router’s network settings have changed or if there are any firewall settings that could be blocking the connection.
  • Ensure there are no MAC address filters or other restrictions that might block the printer on the router.

Take care and have an amazing day!

 

Did we resolve the issue? If yes, please consider marking this post as "Accepted Solution" and click "Yes" to give us a helpful vote - your feedback keeps us going!

 

Regards

Pallipurath.

I'm an HP Employee.


If this reply helped resolve your issue, please select the Accept as Solution as it helps others in the community quickly find the answer they’re looking for.


And if you found this reply helpful, clicking Yes below is a great way to let us know we’re providing the support you need, as it encourages us to keep improving and sharing helpful guidance.

View solution in original post

2 people found this reply helpful
Was this reply helpful? Yes No
3 REPLIES 3

‎02-05-2026 08:58 AM

HP Recommended

Hi @Jedi3,

 

Welcome to the HP Support Community.

 

Thank you for posting your query.

 

I am sorry that hear that your HP printer is unable to connect to Wi-Fi and was working previously, I would request you to please follow the steps:

 

Power Reset

  • With the printer ON, unplug the power cord.
  • Wait 60 seconds.
  • Plug directly into a wall outlet (avoid surge protectors).
  • Restart your router as well.

Restore Network Defaults

  • On the printer control panel:
  • Press and hold Wireless + Cancel for 5 seconds.
  • This clears old Wi‑Fi settings.
  • The wireless light should start blinking

Enable Wi‑Fi Setup Mode

  • If the printer has a touchscreen:
  • Go to Setup → Network → Restore Network Settings.
  • If button‑based:
  • Hold the Wireless button until the light blinks.
  • The printer is now discoverable for ~2 hours.

Reconnect via HP Smart App

  • Install HP Smart on your phone or PC.
  • Tap Add Printer → select your HP 6400.
  • Enter your Wi‑Fi SSID and password.
  • Wait until the wireless light turns solid

Update Firmware

  • Connect the printer via USB to your PC.
  • Download the latest firmware from HP’s support site for the 6400 series.
  • Run the update utility — this often fixes sudden Wi‑Fi dropouts.

Re-add the Printer:

  • On your computer, go to "Devices and Printers" (or similar menu) and remove the printer. 
  • Then try re-adding the printer using the "Add a printer" option, ensuring your computer is on the same network.

Change Network Settings:

  • Check if your router’s network settings have changed or if there are any firewall settings that could be blocking the connection.
  • Ensure there are no MAC address filters or other restrictions that might block the printer on the router.

Take care and have an amazing day!

 

Did we resolve the issue? If yes, please consider marking this post as "Accepted Solution" and click "Yes" to give us a helpful vote - your feedback keeps us going!

 

Regards

Pallipurath.

I'm an HP Employee.


If this reply helped resolve your issue, please select the Accept as Solution as it helps others in the community quickly find the answer they’re looking for.


And if you found this reply helpful, clicking Yes below is a great way to let us know we’re providing the support you need, as it encourages us to keep improving and sharing helpful guidance.

2 people found this reply helpful
Was this reply helpful? Yes No

‎02-05-2026 09:20 AM

HP Recommended

Thank you for the solution what I found out was Verizon changed my  routing number so I had shut off my computer all night and then when I re-plugged it in and did all the other steps I was able to connect it so from them changing the router number made a difference in my printer only so thank you for the information

Was this reply helpful? Yes No

‎02-05-2026 03:01 PM

HP Recommended

Hi @Jedi3,

 

Thank you for responding.

 

I’m glad to hear that the issue has been resolved successfully.

Please feel free to contact us at any time if you face any further issues or need additional assistance. We will be more than happy to help you.

 

Take care and have an amazing day!

 

Did we resolve the issue? If yes, please consider marking this post as "Accepted Solution" and click "Yes" to give us a helpful vote - your feedback keeps us going!

 

Regards

Pallipurath

I'm an HP Employee.


If this reply helped resolve your issue, please select the Accept as Solution as it helps others in the community quickly find the answer they’re looking for.


And if you found this reply helpful, clicking Yes below is a great way to let us know we’re providing the support you need, as it encourages us to keep improving and sharing helpful guidance.

Was this reply helpful? Yes No
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