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.