Can't access certain websites, flushdns solve the problem

Posted on 2011-04-28
Last Modified: 2012-05-11
Hi everyone,

After once Comcast and our IT vendor did something on the router, our Internet starts to act wired. Sometimes we can't access certain website, or it just shows only the text of webpage(no pictures, no styles).
Today, it happened to me again. I couln't ping the website. So I did some research, try to tracert the website, it looks fine. Then I tried flush dns, it solved the problem.
I just wonder what cause this problem and how can I solve it.

Question by:zzl630
    LVL 8

    Expert Comment

    What websites are you having trouble with.  I have found this issue with some bank websites and with cached dns records.  Also do you have a proxy or does your ISP have a proxy/cache server. I have found that these can cause issues also.  I have had to call one isp and have them exclude sites from their proxy/cache server.

    Author Comment

    Website I have known with problems:

    Sometimes I have problems with facebook and ebay too.
    I don't think we have a proxy. Like I said it is just a two-three hours off, then it will back to normal.

    Author Comment

    This is happening right now today.
    Can't access

    Ping request could not find host Please check the name and try agai

    Server:  UnKnown

    *** UnKnown can't find Server failed

    Unable to resolve target system name

    Tried flushdns, doesn't work.

    Tried contact comcast. They said everything is fine.

    Any suggestions?

    Author Comment

    Other websites seem working fine.

    Accepted Solution

    DNS was setted up wrong.
    Try to get the correct dsn from Comcase or use

    Author Closing Comment

    Solved by my self , after searching on other website

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