When i am signing in to yahoo it is showing as 404 not found what that means?

A 404 error means page not found. Either you don't have a connection to the net or the address you're trying to reach is either down or misspelled.

The 404 or Not Found error message is a HTTP standard response code indicating that the client was able to communicate with the server, but the server could not find what was requested.

The web site hosting server will typically generate "404 - Not Found" web page, when users attempts to follow a broken or dead link, hence the 404 error is one of the most recognizable errors users can find on the web.

A 404 error should not be confused with "server not found" or similar errors, in which a connection to the destination server could not be made at all. A 404 error indicates that the requested resource may be available again in the future; however, the fact does not guarantee the same content.

The 404 or Not Found error message is a HTTP standard response code indicating that the client was able to communicate with the server, but the server could not find what was requested. A 404 error should not be confused with "server not found" or similar errors, in which a connection to the destination server could not be made at all. A 404 error indicates that the requested resource may be available again in the future.

Try to play another video if that shows 404 error so it means there is some problem in your internet connection. And if the video play so it means the video whcih you want to play before and showing 404 error is removed by the copyright rules violation on you tube.

it shows invalid mail id or password

If this happens often it may be that your version of yahoo mail needs to be updated. If its the first time you have seen this it is most likely a technical problem with yahoo.

its mean tha the the server can not find the requested page

Hi.

Try doing the reset suggested here: 404 error page not found means that ....
In addition clear cookies and browser offline content.

Try also testing with an alternative browser like Opera

it means that there is a forbidden error... it occurs if u use the wrong link or if there is no response from the server due to some reason (like busy server)...