windows 10 seems to have failed to install proper LAN driver for the chip on your motherboard. Everyone is discovering in many failing ways that Win10 is loading some generic driver files, replacing the original motherboard specific files, thereby creating problems in some areas like wifi, LAN, USB connections, etc.
Next time you upgrade, have all the driver files for your motherboard or computer manufacture supplied ones on hand and add then into the win10 install next. That will hopefully solve the problems
I apologize in advance for any errors in the message as this is coming off my phone. As per the title I am failing to connect to the internet after upgrading to Windows 10 from Window 7. Here are some background system information. I run an old Asus G72GX on Windows 7 x64 bit, 6GB RAM, and a Intel Core2 Duo. My wifi driver is Atheros AR928X and my LAN is Realtek PCIe GBE. Now that those are out of the way lets get to what happened. As I said before I updated to Windows 10 and failed to connect to the wifi upon the update (never even partially, just never connected). I looked for fixes and found the cmd.exe solution with the old VPN. I've never set up a VPN, but I figured it was worth a shot. As expected it failed and when I went to the regedit the was no files pertaining to the Microsoft fix. Next I uninstalled and reinstalled all my drivers and that still failed. I then searched for new drivers and I currently have the most up to date drivers. I then reset the TCP/IP through netsh cmd. I then turned to power saving settings to maximize wifi priority and prevented the system from disabling it. After that also failed I then unchecked the check for the ipv6. Keep in mind I'm restarting the computer after every step to try and point the issue. Finally I rolled back to Windows 7 to see if the connection would reconnect and it didn't. After cleaning up some files and reverting my computer back to the way it was failed I finally decided to restore my computer from a previous date before I updated the OS. That didn't as well and now I'm stuck and looking for additional help. I'm relatively decent with computers, but the simpler the better, especially for other people who may experience similar problems. Just some other comments that may help you help me. There are no issues with wifi, router, ISP, or anything outside this singular PC. Hard connecting the computer also has the same issue and does not connect either. I currently can not upgrade back to Windows 10 until the wifi connection is reestablished. I do have access to internet downloads via my phone if necessary. And finally please don't suggect taking the computer in. Thank you taking the time to read this, I appreciate it.

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