HP Officejet Pro 7740 Scanner loses connection with computer

[RbakerPC]

I have an HP OfficeJet Pro 7740 wide format printer/scanner that was just installed on a brand new Windows 10 HP laptop, everything fresh brand new installs. The printer is directly connected via the local network using DHCP for IP assignment. The printer works perfect with no issues. My problem is with the scanner. It all works great after a clean system boot and reset of the printer but after I use the HP Printer Assistant to scan a few documents and then close the app when I try to restart the app some time later to scan another document the scanner will not respond. I get an error that the software is unable to communicate with the scanner. Yet the printer still works just fine when this happens, it's just the scanner that no longer works. Even if I try Scan-to-Computer from the printer it still doesn't work, get basically the same error.  If I reboot my computer and power cycle the printer everything works just fine again. The problem is intermittent, it work some times but most of the time it fails. My computer and printer are always on, powered on 24/7. You would think I should be able to connect to the scanner any time I need it without have to reboot everything. Any ideas on a solution? Tried reinstalling software, etc. but nothing seems to help.

[greenturtle · Accepted solution]

Hi,

Thanks for using the HP Support Community.

Can you try using a TCP/IP port?

Create a 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)

Hope that helps!

[RbakerPC]

Thanks, setting up the TCP/IP port and using a fixed IP address seems to have fixed the scanner issues. It has stayed connected for over 24 hours with no issues. It would certainly have failed by now with the original setup.

[RbakerPC]

Well it worked for about 36 hours and now it's failing again. Scanner not responding error, have to reboot everything to get it working again. Had an Officejet 8600 previously and never had this issue. Ever since getting the 7740 wide format unit I've had nothing but troubles with the scanner staying connected.

[RbakerPC]

The fix worked for about 36 hours and now it's failing again like before.

[greenturtle]

Hi,

Can you try to use a static IP address?

This resource will be useful:

https://goo.gl/m4hexn

Hope that helps!

[RbakerPC]

I already had an fixed IP address assigned when I created the TCP/IP port.

I noticed last night that IPv4 and IPv6 were both enabled so I tried disabling IPV6 and use only IPv4. That seems to have made an improvement, the scanner is still being recognized this morning. I'll keep checking it and see if that fixed the issues.

Thanks again for the ideas.

[RbakerPC]

Well the scanner lost connection again this morning when I checked. It had been working just  fine all last night. I tried turning off a few other unused/unneeded network features and I'll see what happens now. I did notice that this time I only had to power cycle the printer and I was able to communicate with the scanner again. At least I didn't have to restart my laptop too. So something improved but it's still an inconvenience.

[RbakerPC]

I finally broke down and called HP customer support. We determined that the HP Smart app can scan just fine even tough the HP Printer Assistant app cannot scan. We ran into an issue with the Windows Image Acquisition Service which was yielding an error when we tried to stop/start or restart. So tech support says it's a windows issue and nothing wrong with the printer or HP software. My question is regarding the WIA software which I thought was part of the HP drivers ???? 

I'd be ok with the HP Smart app if I could do what I want but it just doesn't support the features/tasks that I can do with the HP Printer Assistant app for scanning. That allows me to use 200dpi scanning with preset scan sizes and the ability to automatically save the file to a folder on my computer, etc. The HP Smart app cannot scan at 200 dpi, cannot scan custom size images, only fixed page sizes; can automatically save files to a folder without first wasting time to preview, etc. etc. The HP Smart app just cannot do what I need to do and it's WAY WAY to slow when I'm trying to scan a large number of items. This is just so frustrating and right now I cannot get the scanner to work again even after rebooting the computer and power cycling the printer. It's totally non-functional right now unless I use HP Smart and that's useless as well.