SOLVED! HP Officejet 6500A E710 will not stay connected to the network. scanner not connected

Question

After 5 hours of live remote HP tech support, and 10 more hours of web searching, I am happy to say I have solved the wireless network connection issue with scanning and printing using the HP Officejet 6500A E710n-z.  I notice that there are a lot of people with similar issues with no common, successful fix.  Here is what worked for me.  
Background Info:
Upgraded internet service from 9Mbps to 27Mbps...Provider brought out new Arris DG860 modem/router.  Configured network and connected all clients (smart phones, PCs, Tablets, etc) successfully accept the printer.  With this new router/modem the printer/scanner/fax would not connect to my PC at all (Windows 7 64-bit).  The Officejet was always connected to the network, however, anytime I tried to print I would get an error "Unable to connect to the printer...", and when I made an attempt to scan.."Scanner not connected, make sure it is connected to the network..." blah blah blah.  
Process:  
After searching the web for solutions with no success, I finally made my first call to HP tech support.  Tech tried numerous fixes: many network changes (channel, static IP, etc.), made changes to Windows system settings and registry, installed new software and drivers, ran the scan doctor, partial, semi, and full reset on the printer.  He changed my wifi channel to 6 (or 11) from AUTO and whola.  That seemed to fix the problem.  After hanging up the phone 10 minutes later "No connection" errors again.  Made a second call to HP Tech Support, and this new tech basically tried all the same fixes as the first tech.  Worked again for 10-15 minutes then disconnected.  Made third call to tech and this individual tried the same fixes as the previous two, but to no avail.  He said he would have to direct me to a more Advanced Technician and would call back tomorrow.  They called back the next day, and this new tech fixed the issue within 20 minutes. 
Problem/Solution:
The fourth "more advanced" tech made one change in my network configuration settings.  He changed my network mode from B/G/N to B/G and now the printer/scanner/fax stays connected and works like brand new.  The only problem is that all my devices (including the Officejet) are 802.11N capable.  Setting my network to the old B/G mixed mode slows my speed down just a bit.  Using B/G/N mode or N, my download speed is 27 Mbps.  On B/G mixed my speed is 25Mbps.  Not too big of a deal, though.  All the HP Support Techs were very nice and helpfull.  They refunded my $25 Tech fee [fee charged when product is out of warranty] because the problem is not "technically" solved, even though it does work.  Conclusio:  This seems to be an issue with my the modem/router provided by my ISP.  Could also be that it is an older Officejet and need to upgrade.    To Fix Follow the Steps Below:
Step 1:  Find your default gateway IP...usuall 192.168.0.1 or 192.168.1.1 or similar.  Type this IP into your web address bar and hit enter.
Step 2:  Enter the username and password.  This is normally set at factory default --> username: admin ....passowrd: password .... or .... admin
Step 3: Go to the "Wireless Setup" tab and under the "Advanced Options" and "Wireless Network Settings" change the "Wireless Mode" to "B/G mixed".  
Step 4:  Click "Apply" then close the browser.
You may, or may not, lose your wifi connection for a short period while the new settings are applied and you may, or may not, have to power cycle your modem/router.  That's it.  Worked for me and I hope it works for you too.  If you have any questions or comments please feel free to post. 

Answer 1

OK, that all sounds right.  Here are a few more router config ideas:
1. Make sure that 802.11g mode is available, along with others is OK, but 'g' must be present.
2. Change the channel to 11.
3. Use WPA or WPA/WPA2 encryption, not WPA2 only.
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