i work with an ISP. we have a client who is not able to access certain websites but can access other websites. what can cause this to happen

i work with an ISP. we have a client who is not able to access certain websites but can access other websites. All other clients who subscribe to our services are okay.

1) what are the likely things that can cause this problem to happen and

2) what are the ays to resolve them
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

JohnBusiness Consultant (Owner)Commented:
If all generally works for you and if ALL works for the client when not using your service, then check DNS. Likely old DNS settings are causing the issue. That is where I would look first.
nchofulAuthor Commented:
i did that. i gave them the IP address of cnn.com ie to browse with instead of the domain name but it didnt work meanwhile others websites are accessibe.
Network ZeroCloud Engineer Commented:
Have the guy run the command  as admin from command prompt iconfig /flashdns

If he can't do that - deactivate the NIC card and Re-activate it then reboot.

Also ask the person that they aren't on wireless and the lan and make sure there connect to the same place.

If all else fails have him add google's DNS. to his router or nic card

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Internet Protocols

From novice to tech pro — start learning today.