DNS error on one computer in network

[sepand]

I keep getting DNS errors when trying to use the internet on an iMac on my network. The DNS errors sort of come and go. RIght now it's fine, but 5 minutes ago it wasn't. It keeps happening. Now that I think of it, this iMac sometimes also has issues connecting to the internet. One second it's working, then suddenly browsing the internet just times out. Again, every other computer on the network would work fine though.

I'm behind a wrouter that's connected to a modem. How can I begin to figure out what's the issue?

Thanks in advance.

 

[Jad Chaar]

Which OS X are you using? Try flushing the DNS cache: https://support.apple.com/kb/HT5343

 

[DelJo63]

Is your connection via ethernet cable or via the WiFi(Airport).

If cable, replace it, if WiFi, look for interference from external sources.

 

[DelJo63]

You might like to download WifiRadar as a tool to investigate Mac WiFi access.

The PC equivalent is inSSIDer

Look for several stations on the same channel you use and then MOVE yours to avoid as much as possible

 

[sepand]

The problem stopped by itself, as it usually does, until it appears again. For now, all is fine, although I did flush the DNS cache.

My connection is via Wifi.

I'm still going to install WifiRadar. It sounds pretty neat. And I'm on OS 10.6. Thanks.