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Pat, Mac Enthusiast
Category: Mac
Satisfied Customers: 171
Experience:  10 years of systems administration experience in mixed Mac and Windows environments
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I use a Macbook OSX running Safari now. I have also used Firefox

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I use a Macbook OSX running Safari now. I have also used Firefox (prefer it). As of yesterday, neither browser would connect with, which I use daily. I can connect to it using computers and my iPhone. I suspect a virus or trojan horse. What is the best way to check for this? Could it be something else?
You've got 2 questions open, which one would you like to talk to me on? Please answer the following:

Can you open a terminal window. This is done by clicking on spotlight and typing "terminal" without the quotes and then pressing enter. At the prompt, type the following (hit enter at the end of each line):


Report back to me with what it says.
Customer: replied 7 years ago.

** server can't find NXDOMAIN

** server can't find NXDOMAIN

Open System Preferences and click on Network. Then click on "Airport" or "Ethernet" (whichever one you use to connect to the internet). Then click "Advanced" and click on the "DNS" tab. At the bottom left of that window you will see a "+". Click on it, and put the address, then click it again and add as pictured here:


Click OK, then Apply, and see if that fixes it.
Pat and 2 other Mac Specialists are ready to help you
Customer: replied 7 years ago.
I followed instructions as far as I could get: System Preferences, clicked on Network. Can't progress beyond the Airport, i.e. could not locate where to click on Advanced. Help!
Customer: replied 7 years ago.
I checked the "larger image" you included and cannot reach that point. Where you show Airport and then the bubbles next to it, the bubbles are labeled differently on my screen/version
Customer: replied 7 years ago.
There is a TC/ICP bubble that gets me to DNS Servers information screen. No simple DNS bubble to use.
What version of Mac OS are you running? It doesn't matter how you put those DNS server addresses in, you just need to get them in there.
Customer: replied 7 years ago.
Customer: replied 7 years ago.
Believe me, I WANT to put the DNS server addresses in, but where you put them in seems to be something important. Seems to easy to mess things up.
I can't remember how to do it in Tiger exactly. Can you possibly send me a screenshot of your network control panel? Hit command-shift-4, this will give you a targetting thing that you can use to select the area of the screen you want to capture. Then, when you write back to me, you can hit this button graphic and attach the screenshot to me.
I forgot to tell you, it drops the screenshot as a file on your desktop.
Customer: replied 7 years ago.
Got the screenshots with the instructions you gave, but attaching it here is not working. I used the hypertext you gave and a large white page opens up with a teeny icon in the upper left corner. I think this Tiger OS is hard to work with since you have the newest version probably. Can you look at my computer while I'm on it?
Use these directions, but substitute the DNS server addresses I gave you for the ones shown in the guide: