And it does not matter it worked before. Try putting your web server on another port other than 80 or 8080.
I am running an apache2 web server on LinuxMint 17.1. It has been running for a couple of years without issue (on earlier and current versions of Linux Mint). It is a personal wordpress site for sharing family genealogical and other family history. Hence, it doesn't get a lot of traffic. My system consists of a DSL modem ,router and two wired machines and two wireless machines. All of a sudden I'm getting strange behavior, when I try to access my website on a local machine, the DNS, instead of resolving to my URL seems to resolve to my DSL modem management website, routerlogin.com. Their login dalog box pops up. Running a portscan doesn't produce any questionable results. I went down to our local hot spot (McDonald's parking lot) and with my iPad and got a message that the "server stopped responding". Was not able to raise my site at all. I have apache2 installed and configured on a separate partition on Linux Mint Mate 17.3. Switching over to this server produces the same results which tells me that the problem probably lies with my modem/router setup. Incidentally they are both Netgear and are not real old..
I have checked with the DNS provider and the DNS servers seem to be ok.
I have checked the modem and router setup and all seems to be ok. Any ideas as to what to look for will be appreciated

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