printer going offline after a while and have to be restarted (power it off and on) to work again.

[HamidF49]

printer going offline after a while and have to be restarted (power it off and on) to work again.

[Dragon-Fur]

@HamidF49 

It sounds like the printer is falling off of your network.

As an easy "start here" idea, Restart everything, including your network router.

and / or

Download and run the Print and Scan Doctor - this version:

ftp://ftp.hp.com/pub/printers/hppsdr/patches/HPPSdr.exe

and / or

Known solutions here:

Printer is Offline (Windows)

Consider assigning the printer its own static / manual IP address.

Consider assigning a TCP/IP port

References

If you have installation, offline, or port issues, assign a TCP/IP port for the printer

Example:

1. How-to “Create TCP Port” Contributed by greenturtle

Create TCP IP port

1. Print a Configuration Page to get the printer's IPv4 address (you can also tap on the wireless icon on the Front panel of your Printer to get the IP address)
2. On your PC, go to Control Panel, from Devices and Printers, right click the printer and left click Printer Properties, select the Ports tab.
3. Click Add Port, select Standard TCP/IP Port, then select New Port and follow the wizard.
4. Type in the proper IP address for the printer.

This video resource will show you how to do it:
Create & Use TCP IP port

Note that you can ALWAYS revert back to the original port that the HP software installed by selecting the HP port under the Ports tab (in Printer Properties)

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Find Your Wireless WEP, WPA, WPA2 Password

Reference and Resources – (More) Places to find help, solve problems, and learn how to use your Printer

Printer Homepage – “Things that are your printer”

NOTE:  Content depends on device type and Operating System

Categories:  Access to the Print and Scan Doctor (Windows), Warranty Check, HP Drivers / Software / Firmware Updates, How-to Videos, Bulletins/Notices, Lots of How-to Documents, Troubleshooting, User Guides / Manuals, Product Information (Specifications), more

When the website support page opens, Select (as available) a Category > Topic > Subtopic

HP ENVY 7640 e-All-in-One Printer series

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