I had problems with  a free McAfee installation from TIME Warner Cable. Once the blue screen of death was overcome in safe mode, I couldn't get on line. After going through half dozen tech support employees from Frontier, one finally got me going.

He stated that the network card wasn't being recognized and that the following would solve the problem.

cmd line entry:
type -   netsh winsock reset

- reboot pc -

cmd line entries:
type - ipconfig

ping.yahoo.com

One idiot said I would have to take the pc to be serviced. Amazing how much time and money  someone with expertise can save.

Are the above cmd entries standard for a network card not communicating?They are and there are many others.

IPCONFIG is afrequently used instruction especially with the ( all ) switch as IPCONFIG/all

Also the ping.yahoo.com should state ping www.yahoo.com instead, but yahoo as a ping location is not a good reference IMO, I always ping www.google.com instead which will show more realistic latencys to that of your fastest response from the site through your internet connection.

Others to share with you are the following that you can check out:

IPCONFIG/flushdns                         ( This flushes the DNS resolver cache. Not used frequently, but sometimes needed. )
tracert www.somewebsite.com      (This will show the routing path to the website from your HOME and can point out latencies)
tracert xxx.xxx.xxx.xxx                   ( Trace Route to an IP so if xxx.xxx.xxx.xxx was entered with 172.16.4.235  IP would route )
IPCONFIG/all                                   ( Most widely used which shows all NICs and info )

*You can add a /? to the end of them as a help switch and see all options available. Any that are unclear google has good references on in the search with examples that you can look at.

There are also others, but these are the most commonly used when trying to identify issues with CONNECTIVITY to the internet. I used tracert before to identify a bad backbone connection for comcast. Each time the route went through a specific hop of theirs it would either show extremely latent delay or wouldnt resolve. Pinging did not show the cause between my home and say www.google.com, but on every like 5th ping to google, it would fail or take forever. I called up comcast and requested to talk with a network admin as for I need to talk with someone with equal IT Admin experience as myself because the person I got was going through flip chart flow charts and did not understand networking. I was in contact with a guy and stated that you have an ISSUE with this hop on your backbone at this IP. Immediately I was met with " Are you a hacker ", there is no way you can know that unless you are hacking our systems. I said NO I am NOT hacking your network, but if you perform a bunch of trace routes to www.google.com from my area you will find that about 1 in 5 tracert tests will hit this based on the dynamic routing of your DNS and many points of presence on the internet backbone, and this one at this IP has issues. I said tracert is included in the Windows OS and is not a hacking tool that is in violation of my service with you my ISP. He then quieted down and said we will check into this. Expecting something to be done about it I figured they would have it fixed soon.

NOPE ... 3 days and the problem remained so I got blown off. My solution was to no longer use my ISP Comcast for DNS but instead use OpenDNS through IPs from MIT and the problem was gone by using a different DNS provider. You can use a different DNS if you find the same problem with your ISP as well.

Glad you got in contact with someone who knew the correct fix for your issue. So many ISPs have people who are just workers and not IT guru's.