Connection Lost

Hi to all, I have the following problem with the connection of my laptop. When I start the laptop and connect to WIFI or LAN, all is fine. But after some time (could be 10 minutes or 1 hour) I start to lose the connection. Sometimes I lose up and download speed and some time just the upload. At...

Every time my friend want's to connect to my server, he get's one of these messages: Connection lost: Internal Exception: java.io.IOException: An existing connection was forcibly closed by the remote host. Connection lost: Disconnected. Sometimes, he gets connected to my server but gets kicked...