problem in receiving pop3 email from my ISP

Hi,

I am new user to this forum. Let me first thank you for giving your valuable time to help me.

I have a network of 170 users. Everything was working fine till last week. All of a sudden due to a virus attack my network crashed and I need to set it up completely from the scratch.

I have three servers, (1) W2K for user authenication and Exchange (2) W2k with ISA and McAfee antivirus (3) Database server installed with ADC.

My users use network to get Internal e-mail, Database access and to get the internet. I have a pop3 email account with an local ISP.

To connect to the internet, I use local ISP with a Dial-up account and then I connect to satellite internet provider for download.

Now my problem is:

My internal email, internet & database is working fine. But I cant retrieve my pop3 email from my ISP. When I use nslookup command to query my DNS. It shows only my local DNS.

And also I cannot ping to any other site, such as yahoo or hotmail from any of my clients. When I tried to get the help from my ISP they told me that it is your local network problem.

So if you have any solution from my problem, Please help me.

Thank you once again in advance.

>> And also I cannot ping to any other site

Then why you consider your internet is working fine?
To isolate the problem, you first need to see if you can reach remote site via IP only, and forget about DNS.
As far as the actual problem, like your ISP said: "that it is your local network problem", you will have better knowledge than us, not under your LAN. You just have to keep asking your ISP for help.
Say your gf is trying to play hide-and-seek and she hided something in your bedroom. If you ask us where that thing is, we really have no clue, it's your bedroom, you just have to seek it yourself, or ask your gf for it.