This is a standard response when the browser gets no response from the web site you are visiting. More about 404 errors here; http://en.wikipedia.org/wiki/HTTP_404
If you get errors from sites like login pages, then as those sites are normally 'secure sites' there may be a problem with your security settings. You don't say which browser you are using, but if it is Internet Explorer try this;
In IE, goto Tools > Internet Options, then the Advanced tab. Scroll down to Security, then look for the "Use SSL" options.
Make sure the settings are as follows;
Use SSL 2.0 - Not selected
Use SSL 30 - Selected
Use TLS 1.0 - Selected
Use TLS 1.1 - Not selected
Use TLS 1.2 - Not selected.
If you changed any, click Apply then OK and test.
Mark
How do I fix a 404 error code? Most of the sites I go to work but I can't login to several accounts like youtube .Any help would be appreciated,thanks

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