After upgrading my laptop to windows 8 my internet stopped working. I was getting error 651 on my windows 8 laptop. After spending approx. 4 days finally I found solution.
I know many users still have this issue after upgrading to windows 8. I have followed below steps.
1) Go to C drive (press windows key and R key on keyboard and Type C:\ and press enter)
2) Double click on Windows folder
3) Double click on System 32 folder
4) double click on Drivers folder
5) find raspppoe.sys and rename it to something like old_raspppoe.sys Make sure do not delete this file as you may need it if this method does not work for you.
6) Find another windows 8 computer and copy this file on USB from C:\windows\sydney32\drivers\raspppoe.sys
7) Paste this file on faulty computer's drivers folder (path C:\windows\sydney32\drivers\)
8) Reboot your computer and try to connect to internet.
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