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It sounds like your printer is losing its connection to your network.
Ideas...
I found a review for this printer dated 2014.
If you are running a Dual Band Network, connect the printer to the 2.4GHz frequency.
What?
Printer might not support Wireless at 5GHz.
Printer might not support or like a Mesh network.
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Dual Band Network - Wireless Considerations
Reminders
Some printers, particularly older models, only support 2.4GHz
Some printers support both 5GHz and 2.4GHz – but not at the same time
Regardless, if the printer won't work or cannot connect to your 5GHz frequency, try 2.4GHz.
If you are running a Dual Band Network,
Check that the router is set up to broadcast all frequencies it supports.
Next,
If your router supports it,
Create a separate SSID named network for each frequency (one SSID named network for 5GHz and one SSID named network 2.4GHz).
and
Connect the printer to the SSID network on the frequency / band you want it to use.
In general,
- 2.4GHz is less fussy about obstacles and supports a longer distance (separation) between router and device (printer)
- 5GHz is faster
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What else?
Offline Condition
Although the printer appears to be switched on, it does not communicate with other devices on your network.
Consider >> Restart All
Restart Everything, including the router that controls your network
Next,
Offline - Known solutions, presented in the order to be completed / considered
HP printer is offline or not responding - Windows / Mac
Section “Advanced Troubleshooting” > Solutions specific to Windows / MacOS / HP Smart (Printer Unavailable)
AND
Troubleshoot a Wi-Fi connection to an HP printer
HP Printers - Using a Wireless Network Test Report
References / Resources
Starting on Page 82
HP ENVY 7640 e-All-in-One Printer Specifications
Connectivity
Connection method | Requirement |
Wired (Ethernet) | Yes |
Wireless | Wi-Fi 802.11b/g/n |
USB | 1 USB 2.0 |
Direct print supported | Wireless direct printing; Memory card slot |
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HP Printer Home Page - References and Resources
Learn about your Printer - Solve Problems
“Things that are your printer”
When the website support page opens, Select (as available) a Category > Topic > Subtopic
NOTE: Content depends on device type and Operating System
Categories: Alerts, 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, Manuals > User Guides, Product Information (Specifications), Supplies, and more
Open
HP ENVY 7640 e-All-in-One Printer series
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